Throne of Bones Achievement in Halo: The Master Chief Collection

In total, there are 41 skulls scattered across the aforementioned Campaigns that must be collected for this achievement. More specifically, there are 13 skulls in Halo: Combat Evolved, 15 skulls in Halo 2, and 13 terminals in Halo 3. These skull collectibles are extremely well-hidden and come in the appearance of an actual human skull. At times, you will find that some are only obtainable for reaching obscure locations via grenade jumps and other advanced tactics. Needless to say, it will take a tremendous amount of exploration to locate these skulls.

These skulls are a unique collectible in that they act as significant gameplay modifiers. When activated via the Campaign Lobby Menu, skulls will alter the way the Campaign is played by either removing your HUD, permanently cloaking all enemies, promoting enemies to their highest rank, or even disabling the recharge ability of your shields unless you melee an enemy. With that said, these skulls are an awesome set of collectibles to hunt down. Take note however that in Halo: Combat Evolved and Halo 2, skulls will not appear while playing in Classic Mode. Once all 41 skulls have been collected, this achievement will unlock.