Assassin's Creed: Rogue Achievement Guide & Road Map

Assassin's Creed: Rogue
Assassin's Creed: Rogue Achievement Guide

Overview
- Estimated achievement difficulty: 3/10
- Offline: 46 [1000]
- Online: 0
- Approximate amount of time to 1000: 30-50 hours [depending on how you manage your time]
- Minimum number of playthroughs needed: 1 [memory replay available]
- Number of missable achievements: None [memory replay available]
- Do cheat codes disable achievements: Yes*
- Does difficulty affect achievements: No difficulty
- Glitchy achievements: No
- Unobtainable achievements: No
- Extra equipment needed: No

*Cheat codes disable saving, which disables most achievements. However, some achievements require cheat codes to be active, so these should be done last.

Introduction:
Welcome to Assassin's Creed: Rogue, the seventh installment in the Assassin's Creed franchise. The game takes place in the mid 1700's in New York and the northern Atlantic ocean, between the events of Assassin's Creed IV: Black Flag and Assassin's Creed III. In Rogue, you'll be playing as Shay Patrick Cormac, a man who betrays the Assassin Brotherhood to join the Templars. The gameplay of Rogue is identical to Black Flag in just about every way. There are two new additions to your weapon arsenal: the air dart rifle and the grenade launcher. The air dart rifle is used to silently shoot sleep or berserk darts at enemies from a decent distance, and is a serious game-changer in the series. The naval combat and missions return, as well as the vast amount of collectibles that is a staple of the AC series. Overall, the achievements are pretty straightforward and simple, with a couple exceptions that may take some effort. Still, it's a simple and enjoyable game, so sit back and enjoy!

Playing the Game, and Managing Your Time:
When you start playing the game, there is a lot of stuff to do. To manage your time most efficiently, there are a few things that need to be done in parallel: main story missions, side missions, fleet missions, and collectibles. Now you could just do them in series, one after the other, but then it will take a long time to finish this game and get all the achievements. First, I'll break down all of the collectibles and similar things that exist in the game, so you know which ones you need to do for achievements, which ones you need to do for Abstergo Challenges (to unlock cheats required for four achievements), and which ones you're welcome to ignore entirely if you have no desire to do more than what's required for achievements.

Here is a list of all of the collectibles and such, along with their rewards, for your reference:

Templar Maps - Abstergo Challenge
Digging all the Maps - Templar Armor, ACHIEVEMENT
Viking Swords - Viking Armor, Abstergo Challenge
Native Pillars - Native Armor, Abstergo Challenge, ACHIEVEMENT
Cave Paintings - Abstergo Challenge
Shanties - no reward
Animus Fragments - Abstergo Challenge, ACHIEVEMENT
Chests - no reward
Hunting Challenges - no reward
Renovations - Abstergo Challenge, ACHIEVEMENT
Blueprints - ACHIEVEMENT (needed to upgrade the Morrigan)
War Letters - no reward
Prosperity - increases to monetary and resource rewards from all sources
Naval Campaign missions - two Abstergo Challenges, Altair Swords
Abstergo Tablets (present day) - set of pistols
Computer Repairs (present day) - ACHIEVEMENT

The most important thing to do in parallel with everything else are the Naval Campaign missions, the missions you send your fleet on. These initially only take ten or so minutes, but the later ones take an hour or more. There are five segments of missions, and each segment is unlocked upon completing a sequence of the main story. To use your time as efficiently as possible, here is the process I recommend for playing through the game to minimize time required for you to unlock all the achievements:

1. Play the game normally until sequence 2 when you unlock your fleet. Go out and attack a Brig and add it to your fleet. You can only send one ship per mission, so multiple ships aren't required.

2. Explore new areas, gather collectibles, loot supply camps and outposts, capture settlements, etc. Each time a Naval Campaign mission is completed while doing the above, go back to your ship and start the next one. Do this until you finish a segment and need to progress in the main story to unlock more fleet missions.

3. Play each memory in your current main story sequence and finish it to unlock the corresponding achievement and more fleet missions.

4. Repeat step 2, capturing forts and gang HQs as well. Renovate buildings and upgrade your ship as you gain collectibles, making sure to start the next Naval Campaign mission as soon as the previous one is done.

5. When you run out of Naval Campaign missions, finish the main memory sequence you're on. Repeat this until you're done with the game and you should finish enough fleet missions for the achievement by the time you finish the story missions, you should have great progress on your collectibles and exploration and your ship should be fully upgraded or close to it. At this point it's just mopping up whatever achievements are left to do.

Farming Money and Resources:
As you play, assuming you follow a path similar to the one described above, make sure you loot every supply camp, outpost and settlement you come across, as they will give you resources that will add up over time. Also be sure to collect Prosperity at every location you go to, since they increase resource and money rewards from every source.

To make sure you always have plenty of money, renovate all buildings that you find as soon as you find them. With renovations at 100%, you'll be making over 30,000 pounds per deposit in the bank. I finished the game after all upgrades and all cosmetic pieces for my ship and I still had around 700,000 pounds, so money is in no short supply.

To farm resources, there are many ways to obtain them: supply camps, settlements, outposts, ships at sea, etc. You'll find though, that metal is the scarcest resource and you always need more for your next upgrade. Once you start to get upgraded, there's no point in wasting your time farming any of the abovementioned places for resources/metal until you've unlocked the "What's yours is mine" achievement for looting 20 convoys. If you don't work on that achievement first, you, like most people, will end up farming convoys after you finish all the other achievements, and you'll end up maxing out your metal cargo in doing so, with all of it going to waste. So if at any point you need more metal for upgrades, see the "What's yours is mine" achievement description for a great way to farm convoys. To put convoys in perspective, the smallest convoy I found was carrying 200 metal, and the largest I found was carrying 400 metal. Doing this will ensure you have plenty of resources for all of your ship upgrades. Most convoys are a frigate and two schooners or a brig and two gunboats, so you shouldn't need much in the way of upgrades to loot them.

Conclusion:
No matter how you tackle it, Rogue is going to require quite a bit of your time to obtain all achievements. This is mainly a result of all of the exploring you have to do and collectibles you need to find, but if you manage your time appropriately it shouldn't be too bad. Overall the game is pretty easy and straightforward. The story is pretty short and doesn't offer too much in the way of overall plot development, but you do have a nice little bridge between ACIII and ACIV. So sit back and enjoy a relatively stress-free experience, and earn achievements while you're at it!

[XBA would like to thank Necrophage33 for this Roadmap]

Halcyon days

10
Complete sequence 1
Story related; cannot be missed.

Sequence 1 consists of the following four memories:

Memory 1 - The Way The Wind Blows
Memory 2 - Lessons and Revelations
Memory 3 - Tinker Sailor Soldier Spy
Memory 4 - By Invitation Only

Complete all four memories to unlock the achievement.
The end of youth

20
Complete sequence 2
Story related; cannot be missed.

Sequence 2 consists of the following five memories:

Memory 1 - One Little Victory
Memory 2 - We The People
Memory 3 - Fiat Lux
Memory 4 - Kyrie Eleison
Memory 5 - Free Will

Complete all five memories to unlock the achievement.
Making new friends

20
Complete sequence 3
Story related; cannot be missed.

Sequence 3 consists of the following four memories:

Memory 1 - The Color of Right
Memory 2 - A Long Walk and a Short Drop
Memory 3 - Circumstances
Memory 4 - Keep Your Friends Close

Complete all four memories to unlock the achievement.
Picking teams

20
Complete sequence 4
Story related; cannot be missed.

Sequence 4 consists of the following three memories:

Memory 1 - Honour and Loyalty
Memory 2 - Armour and Sword
Memory 3 - Scars

Complete all three memories to unlock the achievement.
One legend dies, and one is born

20
Complete sequence 5
Story-related; cannot be missed.

Sequence 5 consists of the following two memories:

Memory 1 - Men of War
Memory 2 - Bravado

Complete both memories to unlock the achievement.
Brotherhood broken

20
Complete sequence 6
(4)
Story-related; cannot be missed.

Sequence 6 consists of the following five memories:

Memory 1 - The Heist
Memory 2 - Caress of Steel
Memory 3 - No Laws But Our Own
Memory 4 - Cold Fire
Memory 5 - Non Nobis Domine

Complete all five memories to unlock the achievement.
No page unturned

20
Complete the final glitched memory.
(3)
Story related; cannot be missed.

The glitched memories are story related but are separate from the main story and provide a flash forward. They are interspersed throughout the main story and are much shorter than the main missions. There are three of them total:

Memory 1 - RGVjb25zdHJ1Y3RlZA0K
Memory 2 - UHJvdGVjdGlvbg0K
Memory 3 - QXNzYXNzaW5hdGlvbg0K

Complete all three memories to unlock the achievement.
Templar then; Templar now

50
Complete the game
(2)
Story related; cannot be missed.

This will unlock after the credits roll, upon completing the game. The game ends after finishing the final glitched memory.
Achieve full synchronization

50
Achieve 100% synchronization in all main missions
(17)
This requires you to complete every main mission and every optional objective within each mission. The memories required for 100% are Sequences 1-6 plus the glitched memory sequence (referred to as "Incomplete Memories" in-game) which also has optional objectives in some missions.

I highly recommend doing each optional objective during your first playthrough, as some story missions are long, and you'll have to replay through the entire mission to get one you missed. As with ACIV: Black Flag, the optional objectives can be obtained across multiple playthroughs of the same mission. So if there are two optional objectives you're having a hard time completing together, you can do one, then replay the mission later and do the second. Compared to previous AC games though, the optional objectives in this game are much easier.

See this 100% guide: FIRST HALF and SECOND HALF.
Capture all Gang HQs

30
Capture All Gang HQs
Gang HQs are similar to Forts in that once you capture one, you control the area and all locations are revealed. They also are represented by the same symbol on the World Map. The Gang HQs are done on foot in a restricted zone controlled by assassins, and you're tasked with killing the leader (an assassin), cutting down the flag, and one other objective typically.

I highly recommend killing the leader first, and doing it while anonymous. Taking on the leader assassin in open conflict is difficult and can be frustrating. Killing him first will make every Gang HQ a piece of cake. Approach on rooftops and kill the leader from above. The rest is easy.
Stalker killer

20
Counter-Kill 30 Stalkers
(4)
See "Denied" achievement description for more information.
Property Tycoon

20
Complete all renovations
(1)
You'll have to progress far enough in the main story to unlock renovations. Renovations are at locations all over the map at a majority of the locations. There are a bunch throughout New York, at least one at almost every location in River Valley, and a few throughout the North Atlantic. They require a small amount of metal and wood, and slightly more stone and cloth. Each renovation you complete will increase your income to your bank, so make these a priority as you find them.

Note that you won't have access to renovations in an area until you've captured the Gang HQ/Fort which is controlling that quadrant of the map. So if you go to a location and can't seem to find the renovation, check to make sure you're in control of that quadrant's fort/HQ.
Dedicated Employee

20
Complete 35 Abstergo Challenges
(6)
There are 70 total challenges available, and you'll need to complete at least 65 to unlock all of the cheats required for the next four achievements, so completing 35 should, for the most part, come pretty naturally with gameplay and completing other achievements. See this Challenges Guide for some detail on some of the more difficult or unique challenges.
Phantom Queen

20
Fully Upgrade the Morrigan
(4)
To fully upgrade the Morrigan you'll need a lot of money and resources. Money will come naturally from completing main missions, side missions, and property income. Resources must be obtained from supply camps, outposts, settlements, and looting ships at sea.

You'll find that metal is the scarcest resource, and you need a lot of it to get all of the upgrades. Metal comes in high supply from naval convoys, so take every opportunity to loot convoys when you find them. Settlements also provide decent metal, as do Man-O-War ships in the northeastern quadrant of the North Atlantic, and convoys, which can be looted using methods described in the "What's yours is mine" achievement description.

Most of the elite (final-tier) upgrades require a blueprint to unlock, similar to Black Flag. Thankfully these are not underwater and are much easier to find, as they appear on your map when you synchronize the viewpoint in the area. There are a few that are located behind icicle walls in ice caves though, so you'll need the grenade launcher and shrapnel grenade to obtain them.
Camper

20
Loot 20 supply camps
(2)
Supply camps are little white carts on the map and randomly spawn in locations around the River Valley map. All you must do to loot a supply camp is get to the chest in the restricted zone and open it, which you must be anonymous to do. The chest will give you some resources. You can simply fast travel to each location where one spawns to farm them.
What's yours is mine

20
Loot 20 ship convoys
(18)
The first important thing to note is that there are TWO types of convoys that you can loot for this achievement: Royal convoys, which are British ships from the Royal Navy, and French naval convoys. The Royal convoys have a black box on the white sails; the French convoys have a black fleur-de-lis on white sails. Each convoy will be a group of three ships sailing together, and you'll have to loot 20 of these sets of three for the achievement.

The second important thing to note is that you need not actually board every single ship for this achievement, you just need to loot them. That means you can sink every ship as long as you loot the floating cargo when you're done, and you'll still get the achievement. You'll know you got one looted toward the achievement as you'll see the auto-save kick in after you loot the convoy's cargo.

These spawn randomly, and infrequently. One way to make them spawn is to pay a bartender in a tavern for information. The taverns in the North Atlantic (there are three of them) will guarantee a convoy spawn; the taverns in River Valley will give you supply camp locations, and the taverns in New York will give you either (although more likely supply camps). So use the North Atlantic taverns to spawn convoys until they stop giving you intel. When the convoys are identified by the bartender, you can fast travel near their location without them disappearing.

Once you stop getting intel and need to farm them, here is a method that works flawlessly, and almost guarantees a convoy spawn every time (I take no credit for this method; I have compiled it from various sources and my own experience using them):

1. Fast travel to any viewpoint in New York
2. Fast travel to Anticosti in the northwestern corner of the North Atlantic map.
3. Pull up your map and look for a grouping of three ships, one bigger one sailing slightly in front of the smaller two. They often spawn just south of Anticosti or just northwest. Mark the middle ship and sail towards it and sink it, then loot the cargo.
4. When done, or if there isn't one, fast travel to Fort Louis in the southeastern corner of the North Atlantic. Again check for a trio of ships south of you.
5. When done, or if there isn't one, return to step 1.

With this method, I got a convoy to spawn at Anticosti every single time. At first they were spawning just south of Anticosti, about four in a row. Then they stopped and I thought my luck ran out, but the spawn just changed to the northwest side of Anticosti, where I got 8 in a row and unlocked the achievement. Just remember the convoy is likely to be a French convoy in that area, so look for the black fleur-de-lis on white sails.
Do not want

20
Counter 20 smoke bombs successfully using a gas mask
(5)
Once you progress to at least Sequence 3, you'll be able to obtain this achievement. The British enemies (red arrows on the radar) don't use smoke bombs. It is the assassins (orange arrows on the radar) that use the smoke bombs when you're in conflict with them, and only the agile enemies. The agile enemies are the ones without a hat with their hair tied back, and they attack with a knife. When they throw a bomb, you'll be given the option of pressing to put on your smoke mask to guard against the smoke. You'll have to do this 20 times.

The easiest way I found to farm this is to fast travel to the Waterfront HQ in southern New York. Head north past the viewpoint along the waterfront, and you'll come to a lone agile assassin (orange arrow) on the one pier on your right. Engage him, and you can farm all 20 smoke bombs on this one enemy without reloading or fast traveling. When he attacks you, counter it with and then press again to throw him away from you. This should trigger him to throw a smoke bomb. Put on your mask with , and each time he attacks, throw him away again after countering. Once the smoke dissipates, he'll throw another bomb at you after you throw him away, and you can repeat until the achievement unlocks.
Repairman

10
Repair all computers in Abstergo Entertainment
(8)
In the "Present Day" setting, there are 20 computers that need to be repaired. Each repair is a puzzle, and all computers use the same puzzle format. They involve turning rings emitting light rays around a central core to power the core in each section. Once you get the hang of it they're very easy, just focus on the special rings first that have refractive, reflective, transparent, etc., properties.

You won't be able to access all 20 computers until you have level 3 security clearance at the end of the game, so you can either do this as you get kicked back to the present day each time or save it all for the end. If you're having a hard time keeping track of which computers you've done, press to pull up your tablet, and any computers you haven't repaired will show up on your map on your tablet when you're nearby.
Cartographer

20
Visit every location in the game
(5)
Each location in the game will initially be marked as a white "?" inside a black square. Once you take control of the fort/HQ of a quadrant, each location will be revealed, and its symbol will be grey. When you've visited a location, the symbol will turn white. This means you've visited the location and can therefore fast travel back there whenever you want. If you complete all activities in a location, it will be blue, but then you've obviously visited it. So just make sure there are no question marks and no grey locations on your maps (New York, River Valley, and North Atlantic).

NOTE that you won't be able to unlock this achievement until you complete the game, as the final memory of Sequence 6 takes you to the last location in the game.
Ancient Hero

20
Get the Native Armour
(1)
This achievement requires you to find and solve every Native Pillar in the game. They are listed as "mission items" at each location.

You'll typically have to climb your way to each pillar, then solve a very simple mini-puzzle to unlock the pillar. Once you find and solve every Native Pillar, return to Orenda in River Valley to unlock the door, and collect your armor.
Knight of Yore

20
Get the Templar Armour
(3)
To get the Templar Armour, you'll first have to find all of the Templar Maps in the game. These are listed as "mission items" at each location, and they appear as tiny maps on the world map.

Once you've collected each map, you'll then have to find the treasure location that each map points to, using the coordinates in the corner of each map. Make sure you're on the same world map as the Templar Map (i.e. New York, River Valley, or North Atlantic).

Once you've dug up all of the Templar maps, head to The Sapphire (North Atlantic, northeastern quadrant) to collect the Templar armor and unlock the achievement.
Globe Trotter

20
Complete 17 story missions in the Naval Campaign
(3)
The Naval Campaign is the fleet missions from Black Flag. There are 33 unique missions (missions can be replayed as many times as you want); you only need to complete 17 missions for this achievement, but completing all 33 will finish two Abstergo challenges. You'll need to complete every challenge but 5 for all of the cheats, so up to you if you want to complete all 33 of these.

The missions require no effort on your part other than a lot of time, so start doing them as soon as they're available, and as soon as you complete a mission, send your ship on the next available mission as soon as possible so you're constantly working on them. There are five subsections of missions, and you'll have to progress enough in the story to unlock the next set of missions. Also, the requirements for each mission increase as you progress: at first you'll be able to complete missions with a schooner, then you'll need a brig, and eventually you'll need a frigate and then a man-o'-war to have the firepower, speed and storage capacity that the mission requires. So as soon as you're upgraded enough, be sure to add as high a level ship as possible to your fleet. Since you can only send one ship per mission, you don't need to worry at first about having a fleet full of men-o'-war. Just get a brig to get you around a third of the way through the missions, then get a frigate and eventually a man-o'-war when you're pretty upgraded.
Memory collector

20
Collect all Animus fragments
(1)
There are 200 Animus fragments to collect, and they are listed as "collectibles" at each location. They are found in a few different ways:

- On land at each location: these are obtained on foot and are typically high up, requiring you to climb up and either jump down with a Leap of Faith to obtain, or jump from high point to high point.
- Inside Ice Bergs: these will show up on your World Map when you take over the fort/HQ in that quadrant. Once the fragment is revealed on the map, shoot the ice berg or ram it, and then sail through the debris to collect it. These fragments are considered "uncharted Animus fragments"
- On small, uncharted islands: these will show up on the World Map likewise when you take over the fort/HQ in the quadrant. They will be on land but on a small island or cove that doesn't have a fast travel point or view point. You'll have to sail near the land and jump overboard and swim to the land and collect them. Just be careful of the ones in the North Atlantic, as the ice cold water will drain your health while you swim to/from your ship

If you're missing any and aren't sure where to look, hit the Back button and go into your Progress Tracker, scroll over to collectibles and it'll list every area in the game and what you've collected/missed there.
Owned

20
Complete every activity in a single location.
Each location in the game has a list of things that must be collected/completed in that area. This list can be viewed by holding if you're at that location, or hovering over the location on the World Map. Completing every activity will involve finding each chest, animus fragment, templar map, viking sword, completing each renovation, etc. Once you synchronize the viewpoint(s) in a location, every one of these things will be visible on your map, making this very easy to complete in every location; only one location is required for the achievement, however.
For the Empire!

30
Capture all Forts
(1)
Forts are identical to forts in Black Flag, except much easier this time around. Like previously, to capture a fort, you'll first need to destroy its defenses while on your ship. Then you'll have to infiltrate the fort on foot, kill the captain and usually one or two other objectives. Like with Gang HQs, capturing a fort grants you control over the area and reveals all locations, as well as Uncharted collectibles.

To take out the fort's defenses, use a combination of mortars and round shot while sailing around to avoid the incoming fire. It might be a good idea to take out any enemy ships in the immediate area first, although if you leave them incapacitated and your ship health gets low during the fort attack, you can always board the ship in the middle of the battle and use the ship to repair the Morrigan, giving you more health in the middle of the fort battle.

Each fort is located in either an Easy, Medium, or Hard zone, which is displayed on the World Map. None are really difficult, especially if there aren't any other ships attacking you while you're trying to attack the fort, but I recommend having advanced hull armor, bronze mortars and advanced round shot at a minimum before taking on the forts in the Hard zones.
I'll take that

20
Capture all settlements
(1)
Settlements look like little houses with a round roof on your map, and are one-time only captures. When you reach the area of the settlement, you'll be given a couple objectives to complete such as killing the captain, killing snipers, etc. Complete these tasks and the settlement will become a friendly settlement, along with rewarding you with a pretty decent amount of resources. There are only a handful in the game, so capture them all and the achievement is yours.
Master of the North Atlantic

50
All legendary Battles Completed
(39)
There are four legendary battles total. The first three will show up on the World Map in the North Atlantic region as you gain control of each quadrant of the map by taking over the fort/HQ for that area. They'll show up as big red ships near the edge of the map in each corner. The fourth and final legendary battle, which is listed as an "epic legendary battle," is available after beating the first three and will show up in the southwest corner of the map. Naturally you'll want to wait until you've got your ship fully upgraded, or at least close to it, before attempting these battles, as this will be the most difficult achievement in terms of skill required.

The first three battles are relatively easy and shouldn't pose much of an issue if you're fully upgraded. Stick to the tactic of mortar to take out the smaller ships, while sailing toward the legendary ship, charge it with your ram, then turn towards the rear of the ship, hit it with heavy shot while you're next to it, use your puckle gun on weak spots, and then when you circle around to the back of the ship, use your round shot. As the ship sails away to circle back, turn back towards it and repeat the process.

For the fourth battle, it is extremely difficult, at least as difficult as the hardest ones in Black Flag. You will first fight the Storm Fortress, which does insane damage from its broadside cannons and sets you on fire with its mortars. Once you get it down below 1/4 of its health, two more men-o'-war come in to help it. Thankfully the two smaller ones take decent damage from mortar fire and will get destroyed pretty quickly by heavy shot. Focus on finishing off the Storm Fortress first though, as it can inflict heavy damage if you aren't paying attention to it. Then use your standard tactic on the smaller ships to finish the battle.

IMPORTANT NOTE: If you just want this achievement and don't care about it not counting toward the last Abstergo Challenge for getting 100% in everything, you can turn on the Immortal cheat right before entering the legendary battle. Finish the battle (you'll be immune to any damage) and as soon as you're done, turn Immortal off. The game will auto-save and you'll unlock the achievement, but the legendary battle will still be on the map and you won't have gotten credit for it, other than the achievement.
Smashing

10
Destroy 100 Ice Bergs
(1)
In the North Atlantic region of the game, there are random ice bergs throughout the ocean. They can be destroyed by shooting them or by ramming them once you have an upgraded ram. When you destroy them, they have a chance to contain cargo/resources inside for you to loot, which is a nice bonus. They will also create ripple waves when you destroy them, which are capable of damaging gun boats and schooners.

The story missions don't take you through the North Atlantic very often, so every time you are sailing in that region, shoot at every ice berg you get. It'll be less work to come back later sailing around just to destroy icebergs.
Ice Breaker

10
Break through 500 meters of Ice Sheets
(1)
Ice sheets are also located in the North Atlantic region of the game. You won't be able to break through ice sheets until you've upgraded your ram at least once.

500 meters may seem like a lot, but I literally broke through a strip of ice 2 or 3 times and I got the achievement, so this one comes really quick. If you see an ice sheet in the North Atlantic when you're there, head toward it and plow through it a couple times and you should have the achievement right away.
Freedom Fighter

20
Free 300 British PoW's
(13)
Once you progress enough in the main story (although it is not introduced in the main story), PoW ships will show up on your map, mainly in the North Atlantic region, as a fist inside a black circle. The PoW ship will be being escorted by two other ships, usually brigs, which will be marked with red dots to sink them. Your goal is to sink the two escort ships, then board the PoW ship to free the PoWs. During the sinking of the escort ships, any damage you do to the PoW ship will kill PoWs, lowering the amount you can rescue from that ship; it always starts at 100 and will drop from there. The boarding process of the PoW ship is like any other ship.

Since the ships carry 100 PoWs, you'll need a minimum of three ships to get the achievement, but since you'll almost assuredly kill some PoWs in the process, you'll likely need 4-5 ships for the achievement. If a PoW ship does show up at a certain spot on your map, DO NOT fast travel to a nearby location to be closer to it. That will make the ship disappear. You'll have to sail directly to it and then attack it.
Unicorn Slayer

10
Harpoon a Narwhal
(3)
The Narwhal is located in the North Atlantic region of the game, in the northeast quadrant. It will be revealed on your map when you take control of the fort in that area (Fort Baie Rouge). The symbol looks like a swordfish with a long horn on its nose. You'll want to have a fully upgraded rowboat for this, as it takes quite a few harpoons and it is very wily.
Defence First

10
Survive a Reverse-Boarding
(2)
A reverse-boarding can happen in this game if an enemy ship rams you and your health is low enough. Then the enemies will board your ship. You'll then be given essentially the same objectives as a normal boarding (e.g. "kill 10 enemies"). Complete the objectives, and this will survive the reverse-boarding, as well as give you the enemy ship's resources.

This is more likely to happen naturally in the game early on, when your ship is weak and you're being attacked. I personally had it happen in Sequence 2, Memory 1, where you have to fight the four gunboats, since you're weak and they're likely to ram you. Otherwise, you'll have to pick a fight with a group of ships and sit still and let them ram you and hope for a boarding.

A good way to get this to happen later in the game if you haven't gotten it naturally is to raise your Wanted level. When the hunters attack you, they will always be Assassin ships, and some are likely to ram you and board you. You have to be sitting still or barely moving when they ram you for them to be able to board you though, so slow down and turn your broadside to the hunter and it should ram you and board you.
Denied

20
Counter 15 air surprise attacks
(5)
Once you progress far enough in the story (Sequence 3), you'll be attacked by hidden assassins in various locations. An assassin lying in wait will be indicated by whispers in the background. As you get close enough to the assassin, you'll get a red border around the screen. If you use Eagle Vision, you'll get a compass indicating the direction of the assassin and a relative distance; it'll also indicate if they're above or below you. This compass is identical to the one used in multiplayer from previous AC games.

When the assassin attacks you, you'll see the red indicator above their head indicating you can press to counter their attack. Do so, and then use to get the counter kill. Counter-killing an enemy that tries to air assassinate you also counts toward "Stalker Killer." You'll have lots of opportunities to get these, just make sure that if you've got a stalker nearby, let him attack you and get the counter kill.
King of the Hill

20
Complete all Native hills and Ice Caves
The Native Hills and Ice Caves show up on your map as round archways, just like in the achievement picture. Capturing the fort/HQ in the area will reveal them all on the map. To "complete" them, you'll have to find the Native Pillar and complete its puzzle. Collecting everything in the area isn't required to complete them, but you'll still need the animus fragments and blueprints for other achievements.

Note: Don't bother exploring the ice caves until you unlock the grenade launcher and shrapnel grenade, as you'll need it to break icicle walls to obtain blueprints.
Ninja

20
Complete an Outpost without getting detected
(2)
Outpost icons on the map show up as a symbol for an entire location, and they look like a ranch house with a straight sloped roof. In an Outpost, you'll be tasked with infiltrating, looting a key from a key holder, looting the stash with that key, and then escaping. Some outposts may have as many as three key holders and stashes to loot. To get this achievement, you'll have to complete all objectives without entering conflict.

Naturally to make this achievement easier, you'll want to try on an outpost with only one key holder and stash. Waiting til later in the game will make this easier, when you have berserk darts/grenades and sleep darts/grenades.

If you fail at this, outposts do respawn after a set amount of time, so you can eventually return to the same outpost to retry it. Just take your time, and if need be, take out every enemy.
Instant Vikings

20
Hit 5 enemies with the berserk grenade (at the same time)
(4)
See "Nap Time" achievement description for more information.
Nap Time

20
Put 5 enemies to sleep with the sleep grenade (at the same time)
(4)
You'll need to progress far enough in the main story to unlock the grenade launcher.

The easiest way to get five enemies together is to fast travel to one of the locations in River Valley that has groups of 5 enemies walking together on patrol with a captain in charge. You'll notice these as they are surrounded by a red restricted area circle as they move. Wait til they stop at the end of their patrol (or you can try leading them with your grenade), and then fire a sleep grenade to put all five to sleep. Once they're all asleep, switch to a berserk grenade and fire that to make them all go berserk.
This war of mine

30
Complete all Assassin interceptions
(5)
There are 12 Assassin interceptions in the game. They show up in various locations as a pigeon in a black circle on your map. You'll first be tasked with capturing a pigeon (which is holding an assassin contract), then you'll have to find the target of the assassination, and then protect the target by killing the 7 assassins that are after the target.

Some of the contracts take place in highly populated areas, so before accepting the contract, it might be a good idea to kill red and orange arrows in the vicinity of the target so you don't have to worry about going into conflict during the mission. Also, taking on assassins head-on will be difficult and frustrating. Use Eagle Vision to locate them (highlighted in yellow) and either assassinate them (you can simply walk up to them) or shoot them.

NOTE that there is an assassination interception in Greenwich, New York that isn't available until you finish all the others, so if you're wondering why there seems to be an icon mission on the map, you'll need to finish the rest to unlock that mission.
Hunt the hunted

20
Sink 10 ships in North Atlantic without dying while only the HUNTED cheat is active.
(8)
The HUNTED cheat means Hunter ships will continually hunt you down while active. It requires you to complete 50 Abstergo Challenges to unlock. See this Challenges Guide for some of the more difficult challenges.

See "I ENDURE" achievement description for more information. NOTE though that you cannot do both together, as you need to only have one cheat active at a time to unlock each achievement.
I ENDURE

20
Sink 10 ships in North Atlantic without dying while only the ENDURANCE cheat is active.
(3)
The ENDURANCE cheat means your ship won't regenerate health. It requires you to complete 55 Abstergo Challenges to unlock. See this Challenges Guide for some of the more difficult challenges.

For this achievement, you'll want to have your ship fully upgraded, or at least the mortars, hull and round shot, since you'll need to survive while destroying ships over and over. Don't worry though, if you're fully upgraded, the achievement is a breeze.

Fast travel to Fort Louis in the southeast corner of the North Atlantic map. Pull up your map, and south of you you'll see a bunch of red ships on your map. They will all be gun boats, schooners and brigs. If your mortars are fully upgraded, one well-placed shot will take out each ship, including the brigs. Sail toward them, and right before you engage them, turn on the cheat. Sail around using your mortars to sink ships from a distance until the achievement unlocks. The hunters will get progressively higher as you destroy ships, so if you can avoid the first hunter, you should be able to take out the ten ships required for the achievement before the second wanted level of hunter shows up to attack you. Make sure to turn off the cheat as soon as you unlock the achievement.
Supplier

30
Take over 10 large supply camps while only the VETERANS cheat is active.
(4)
The VETERANS cheat makes all enemies upgraded to higher rank, so they're more deadly and do more damage. It requires you to complete 65 Abstergo Challenges to unlock. See this Challenges Guide for some of the more difficult challenges.

This one is easy since dying does NOT void the achievement, and the game still saves with this cheat on. So fast travel from location to location in River Valley, picking ones that are closest to the supply camps (indicated by a white cart on your map). There should be 3-5 supply camps present on your map at any given time, so you shouldn't ever have to go to a Tavern to find one. You can either approach the chest stealthily, or since dying doesn't matter, rush the chest and fight everyone off. Make use of smoke bombs during fights and berserk darts to clear areas. This one will take a little time but isn't difficult at all.
Killing machine

30
Kill 30 guards without dying while only the ENDURANCE cheat is active.
(4)
The ENDURANCE cheat means you won't regenerate health. It requires you to complete 55 Abstergo Challenges to unlock. See this Challenges Guide for some of the more difficult challenges.

This one is really easy, since you can do it all without entering in conflict. Fast travel to Halifax in the North Atlantic (obviously you should have taken it over by now). There are 11 guards. Assassinate them all, double assassinating each pair together. You should be able to kill them all without entering conflict. When done, fast travel back to the viewpoint in Halifax and all the enemies will respawn. Repeat until the achievement unlocks, then turn off the cheat.

Did I do that?

20
Complete Present 1
(1)
Story related; cannot be missed.

See "Sending A Message" achievement description for more information.
He's not dead, is he?

20
Complete Present 2
(1)
Story related; cannot be missed.

See "Sending A Message" achievement description for more information.
A worthy cause

20
Complete Present 3
(1)
Story related; cannot be missed.

See "Sending A Message" achievement description for more information.
Sending a message

20
Complete Present 4
(1)
Story related; cannot be missed.

The present-day "missions" take place between each memory sequence and are extremely short. You'll be tasked with rebooting a server each time to access more of Shay's memories, and then returning to your Animus.