Here is the full list of all 55 Trapped Dead: Lockdown achievements.
Clear Church Street of all enemies
Finish the game with the Marine on Easy difficulty
Finish the game with the Butcher on Easy difficulty
Finish the game with the Marshal on Easy difficulty
Finish the game with the Assassin on Easy difficulty
Finish the game with the Exorcist on Easy difficulty
Finish the game with the Marine on Normal difficulty
Finish the game with the Butcher on Normal difficulty
Finish the game with the Marshal on Normal difficulty
Finish the game with the Assassin on Normal difficulty
Finish the game with the Exorcist on Normal difficulty
Finish the game with the Marine on Hard difficulty
Finish the game with the Butcher on Hard difficulty
Finish the game with the Marshal on Hard difficulty
Finish the game with the Assassin on Hard difficulty
Finish the game with the Exorcist on Hard difficulty
Finish the game with the Marine on Nightmare difficulty
Finish the game with the Butcher on Nightmare difficulty
Finish the game with the Marshal on the Nightmare difficulty
Finish the game with the Assassin on Nightmare difficulty
Finish the game with the Exorcist on Nightmare difficulty
Clear Main Street of all enemies
Clear the Prison of all enemies
Clear the Junkyard of all enemies
Clear the Train Yard of all enemies.
Clear the Sewers of all enemies
Clear the Suburbs of all enemies
Clear the Riverside of all enemies
Clear the Old Church and Cemetery of all enemies
Clear East Commercial District of all enemies
Clear West Commercial District of all enemies
Clear the Hospital of all enemies
Clear the Factory of all enemies
Clear the Downtown Area of all enemies
Clear the Rooftops of all enemies
Clear the Forest of all enemies
Clear the Caves of all enemies
Clear the Military Base of all enemies
Buy an item from a Trader
Run over 50 zombies with a car
Kill 50 enemies using Melee Weapons
Kill 50 enemies with Ranged Weapons
Get killed on Church Street
Reach Level 5
Reach Level 10
Reach Level 15
Reach Level 20
Reach Level 25
Reach Level 30
Kill an enemy of every type
Destroy 50 breakable objects
Eat 100 food items
Collect 1,000,000 cash
Test Driver
Defeat 150 enemies using the Sharpen Skill