Here is the full list of all 50 South Park: The Stick of Truth achievements worth 1,000 gamerscore.
You collected 5 Chinpokomon.
You successfully blocked every enemy attack in a single (non-tutorial) battle.
You defeated 3 enemies in one battle while your buddy was knocked out.
Over the course of the game, you've blocked 100 attacks.
You have joined the KKK.
You completed your first day in South Park.
You sold 300 junk items.
You've unlocked all of the upgrades for a New Kid ability.
You farted on 10 enemies in the world that were knocked out.
Over the course of the game, you've scored 100 perfect attacks.
You befriended the Goths, like everyone else playing this game.
You collected 15 Chinpokomon.
You flung a turd of your own creation at an enemy.
You defeated the Grand Wizard Cartman in battle.
You opened all of the garages in South Park.
You befriended your father.
You made friends with half of South Park.
You have collected half of the available costume sets.
You've spent $500.
You found Jesus while playing as a Jew.
You shat your pants during a boss battle.
You accepted your fate and chose the name Douchebag yourself.
You defeated Princess Kenny and recovered the Stick of Truth.
Defeat Kyle in battle.
Let Gingers bite you 3 times without blocking.
Defeat the Boss Hall Monitor while wearing freckles.
Summon Mr. Slave while in Mr. Slave's colon.
Sell nothing the entire game.
Defeat Princess Kenny while looking like David Hasselhoff.
Fart on the Mayor, Father Maxi, Principal Vic, & Prime Minister.
Fart on a canine enemy while in Gnome form.
Hit 3 enemies with a single fart outside of combat.
Defeat Princess Kenny while in your Makeover disguise.
Fart on each available buddy in the game.
Interrupt 5 channel attacks with a fart.
Defeat the Meth Tweekers while wearing the Evil Cartman goatee and the bald cap.
Defeat Kenny while sick with Dire AIDS.
Watch your parents have sex for 60 seconds.
Complete the game without ever ending a combat with a buddy knocked out.
Collect all the Chinpokomon.
Befriend all of South Park.
Kill 20 enemies with Cartman's ass.
Fart on people 100 times
Fart on animals 25 times.
Shit Your Pants in battle three times.
Complete all available Costume Sets.
Fart on the corpse of an aborted Nazi Zombie fetus.
Befriend Crab People and Underpants Gnomes.
Have Kenny Die 10 times in battle over the course of the game.
Collect all the weapons and costumes available in the game.