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