XII - Out of Bounds Achievement in Vampire Survivors

One important thing to point out is that all four achievements for reaching minute 31 can't be unlocked until after you obtain the Randomazzo relic. I'm not sure why that bit of the achievement description was removed in the port over from Steam.

There are two ways to reach the 31 minute mark in a stage: the easy way and the hard way.
 

• The Hard Way - This is the way I've seen discussed in most places, and I have no idea why it seems to be the primary method. To do this, you need to survive the attack from Red Death at the 30 minute mark. The only way this is possible is to first obtain the Yellow Sign relic (refer to I can't see anything... (50G) for getting it), then during the stage you're playing, collect the four new items on the map (Silver Ring, Gold Ring, Metaglio Left, and Metaglio Right). You then need to also get the Clock Lancet and Laurel, both of which count as weapons and therefore fill weapon slots. You then need to get all six of those things (both weapon and all four items) to max level, then open chests to evolve the Clock Lancet into the Infinite Corridor and evolve the Laurel into the Crimson Shroud. Now, when Red Death shows up, the Crimson Shroud prevents you from taking much damage, and the Infinite Corridor freezes Red Death and can more easily kill it. However, it is possible to kill Red Death too quickly, ending the run before you reach the 31 minute mark. So, you need to survive, not kill Red Death. As you can imagine, this is quite stressful and challenging to do, and I don't recommend bothering with this method for any reason
• The Easy Way - First unlock Endless Mode (refer to Greatest Jubilee (50G) for doing so). Then, play each stage with Endless Mode turned on. In Endless Mode, once you hit the 30 minute mark the enemies revert back to the start of the stage, but the clock keeps counting up. Simply survive another minute which should be a piece of cake with just the simple starting enemies of a stage, and then you can quit after 31 minutes and get your achievement. This is far, far easier, and definitely the recommended way to get these four achievements for reaching minute 31.