Here is the full list of all 35 Postal III achievements.
Beat game with zero kills.n(zombies and bosses don't count)
Kill no animals in one playthrough.
Complete Good path without falling off.
Kill/incapacitate 235 terrorists.
Complete game using only melee.
Euthanise 30 elderly folks.
50 kills using bees.
Kill 1000 unarmed bystanders.
Piss 100 gallons of urine.
150 kills using fire.
Spend 900 seconds or more in catnip bullet time.
50 kills using cat.
Destroy 50 cars.
Smash 50 windows.
Arrest 200 perps.
50 kills using boomerang machete.
Respawn 20 times.
50 badgersaw kills.
Suck up 500 items with the shop vac.
100 kills using machete in melee.
Make Venezuela peacemakers go home.
Taze 200 victims.
Take out all the criminal scum infesting Catharsis!
Arrest eco zealots leader.
200 kills using M-60.
300 headshot/decap kills.
Complete game using only the pistol.
Complete game killing only males.
Beat the game once. No restrictions apply. Everyone's a winner.
Finish your business with Krotchy.
Escape from prison.
Return Thegways to the owner
Choose path for the first time.
Disobey orders, given to you, and see what happens.
Injure yourself.