Here is the full list of all 45 Paranautical Activity: Deluxe Atonement Edition achievements.
Beat the second floor.
Kill a Tenchi while it's invisible.
Have more armor than health.
Complete a room without taking damage.
Complete a room without attacking.
Complete a floor without jumping.
Complete a floor without taking damage.
Survive a dark floor.
Complete a hole floor without falling in.
Fall into a hole in a hole floor.
Have 69 bombs.
Have 1000 coin dollars.
Have 30 items at once.
Beat any mode in under 15 minutes.
Run out of superweapon ammo.
Spend all your money gambling.
Let a boss die to poison.
Kill 100 Gileads.
Kill 1000 Jimbaabwehs.
Kill Dahlia.
Beat the fourth floor.
Beat the sixth floor.
Beat classic mode.
Figure out how to get to the 8th floor.
Beat hardcore mode.
Beat any mode with Tank.
Beat any mode with Gilead
Beat any mode with Bouncer
Beat any mode with Gorton
Beat any mode with David Bowie
Beat any mode with Dynomite.
Beat any mode without taking items.
Beat Hardcore Mode with all 6 characters.
Beat hardcore mode 10 times.
Beat 4 floors in a row using only melee attacks.
Beat hardcore mode without spending money.
Beat hardcore mode having gone into every room.
Get a ghost and survive the floor.
Spawn two ghosts at once.
Kill Dahlia after she spawns every set of enemies. Twice.
Kill Dahlia without taking damage.
Kill every boss.
Get every item.
Use every weapon.
Get every achievement.