Full Gameplay Walkthrough...

Complete the indicated task to unlock the achievement.

Achievement	How to unlock
1000 Yard	Achieve 100% completion.
Amazing Chest Ahead	Encounter the chest mimic.
Annihilation	Fully clear the Contamination Area mission.
Blood Meridian	Fully clear the Ghost Town mission.
Bravo Foxtrot Golf	Fully upgrade your inventory.
Col Do Ma Ma Daqua	Unlock the Toxic River challenge.
Dawn of the Dead	Fully clear the Burial Grounds mission.
Devil Trigger	Unlock the Infernal Gate challenge.
Don't Deal With the Devil	Complete the Toxic River challenge.
Galatians 5:20	Unlock the Warlock.
Greed is Good	Buy out the shop.
I Have Friends Everywhere	Visit the secret shop.
Icon of Sin	Defeat the Supreme Overseer boss.
Jamais Vu	Pop the red balloon.
Locked and Loaded	Open the shooting range.
More Room to Doom	Upgrade your inventory once.
Night of the Living Dead	Complete the Burial Grounds mission.
Original Sin	Defeat the Foetid Freak boss.
Press Start	Complete the tutorial.
Quiet Mountain	Fully clear the Mountain Temple mission.
Revelation 20:14	Unlock the Salamander.
Risky Rescue	Unlock a shortcut.
SSS	Complete the Infernal Gate challenge.
Scholar of the First Sin	Defeat the Enhanced Prototype boss.
Sweet Home	Fully clear the Old Mansion mission.
System Shock	Complete the Contamination Area mission.
Temple of Doom	Complete the Mountain Temple mission.
The House of the Dead	Complete the Old Mansion mission.
The Root of All Evil	Visit the shop.
The Suicide of Kras Mazov	Buy out the secret shop.
There Will Be Blood	Complete the Ghost Town mission.
Thessalonians 5:3	Unlock the Ranger.
Trophy Trouble	Unlock all shortcuts.
Vault 101	Open the vault.
Vault Dweller	Fill the vault.