Here is the full list of all 12 Comix Zone achievements worth 200 gamerscore. It takes around 2-3 hours to unlock all of the achievements on Xbox 360.
You received both endings.
You rescued Alissa and completed the game.
You completed Episode 3.
You scored 50,000 points.
You completed Episode 2.
You scored 30,000 points.
You scored 10,000 points.
You finished the first page.
You collected Roadkill.
You used a paper airplane.
You restored your health with Iced Tea.
You used the dynamite.