Here is the full list of all 24 Bedlam achievements.
Kill 5 opponents in the Arena without dying
Destroy all three guard towers in Death's Dark Vale
Defeat Lanzok and free the captive marines
Encounter the Accounts Dept.
Secure Sigma Sector
Destroy the Gaian Comms Jammer
Complete the Graxian combat training and salute your commanding officer
Complete the secondary objective
Complete Rage-Quit Reactor without the Reactor exploding
Exit Star Fire
Reach the end of the Rue de Chambard Rouge
Reach the end of the Boulevard du Burnistoun
Destroy the Armoured Car
Mess with The Valve
Clear the Chilli Comper Maze
Bring down the Super Saucer
Escape from Age of Attrition
Find the fire sword
Defeat the horde
Wish Granted in Planetfire
Complete Planetfire Ascension
Get a Score of at least 3500 in Rescue Run
Complete Rescue Run
Complete the Game