Here is the full list of all 45 Paranautical Activity achievements worth 1,000 gamerscore.
Spend all your money gambling.
Complete a floor without jumping.
Beat any mode with Bouncer.
Beat any mode with David Bowie.
Kill a Tenchi while it's invisible.
Beat hardcore mode going into every room.
Beat any mode with Dy-no-mite!.
Get every item.
Beat hardcore mode without spending money.
Kill 1000 Jimbaabwehs.
Beat any mode with Gilead.
Complete a room without taking damage.
Beat any mode with Gorton.
Beat any mode in under 15 minutes.
Beat 4 floors in a row using only melee attacks.
Have 69 bombs.
Beat Hardcore mode with all 8 characters.
Have 1000 coin dollars.
Kill every boss.
Beat the fourth floor.
Beat the sixth floor.
Survive a dark floor.
Let a boss die to poison.
Use every item.
Have 30 items at once.
Complete a room without attacking.
Have more armor than health.
Get every achievement.
Beat any mode without taking ANY items.
Beat the second floor.
Get two ghosts at once.
Beat Hardcore mode 10 times.
Complete a hole floor without falling in.
Beat any mode with Tank.
Figure out how to get to the 8th floor.
Win a Dahlia fight without taking damage.
Kill 100 Gileads.
Beat Hardcore mode.
Kill Dahlia after she spawns every set of enemies. Twice.
Run out of superweapon ammo.
Fall into a hole in a hole floor.
Complete a floor without taking damage.
Beat normal mode.
Get a ghost and survive the floor.