Reached Monument Island.
In the Main Campaign, killed 25 enemies with the Broadsider Pistol.
In the Main Campaign, equipped a piece of Gear in all four slots.
In the Main Campaign, completed Lighthouse.
Completed Onyx Point
Completed at least 20 Declassified missions
Do 250 rampage kills/kill streaks
Save a team member that is stunned by an electron mace
Reach the pump room of the Waystation without alerting any Feeders.
Complete all optional missions.
Collect all Weapon Parts.
Collect all Circuits.
Face all of Carver's demons by completing all Co-Op only optional missions.
Collect all Artifacts.
Collect all Logs.
Completed Seahorse Hills
Attained 50 Stars on at least Casual Difficulty
Unlocked Aftermath
Completed Halvo Bay Military Academy
Reached level 5
Completed Museum Of Military Glory
Complete the game on Casual
Complete the Campaign using max one medkit per mission
Continue playing to unlock this secret achievement.
Completed your first Declassified mission
Watched Aftermath teaser
Complete Act 2
Kill 15 enemies with a stealth kill
Complete Act 1
Complete any act without using medkits
Take 50 headshots in single player
Kill 50 enemies while holding your breath
Kill three or more enemies by shooting a grenade
Kill 25 enemies using thermal or night vision goggles
Kill 20 enemies from a distance of 600m or greater
Take a successful shot from a distance of 1 km or greater
Complete any single player mission without using med kits, but taking damage
Defeat Putnam.
Kill 25 enemies while staying cloaked.
Use Eagle Flight to travel 1 km.
Solve the Rolling Crusher Puzzle
Win the Buttonless MiniGame against a Juggernaut
Defeat Megaera and the Titan Hecatonchires
Kill 25 Enemies using the Rage of the Gods