Vanquish

Story related achievement BUT it can be missed!

Warning:

• "Complete all Acts" requires playing through all Acts consecutively. If you use mission select at any time in your playthrough, you will not get the achievement for completing the game even though you have literally completed all Acts and have the achievements for each Act! You won't unlock the Living Legend achievement either!
• The same applies to "Complete Act #". If you use mission select before having finished an entire Act, you will not get the achievement related to completing that particular Act. (Thanks to vithzeral for pointing this out).
• When you use mission select, even after you have beat the game, all your weapons will be set to standard settings without any upgrades!

Once you've completed all missions on all acts, you will get this achievement after the credits. The complete list is below.

Act 1:
Mission 1: Landing
Mission 2: Breach
Mission 3: Giant
Mission 4: Rescue
Mission 5: Trust
Mission 6: Darkness
Mission 7: Seismic
Mission 8: Hostile

Act 2:
Mission 1: River
Mission 2: Rapids
Mission 3: Nightmare
Mission 4: Struggle
Mission 5: Assault
Mission 6: Stronghold

Act 3:
Mission 1: Forward
Mission 2: Attack
Mission 3: Vertigo
Mission 4: Dragon
Mission 5: Despair
Mission 6: Infiltrate
Mission 7: Phantoms

Act 4:
Mission 1: Silence
Mission 2: Brink
Mission 3: Maneuver
Mission 4: Slave
Mission 5: Emancipation

Act 5:
Mission 1: Denoucement
Mission 2: Soldier
Mission 3: Deception

See also "ARS Operator".