HEEEEY YOOOOO GUYYYYYSSSS! - 10 gamerpoints - Take no damage on the waterslide.
This game is rigged! - 10 gamerpoints - Shoot everything from the Wheel of Insanity - Balloons and the Cow).

Game On! - 10 gamerpoints - Heh heh, good times.

Game Over! - 20 gamerpoints - Stealth Kill Sinister, in the Prison, with the Sword!.

Patience is not a virtue - 20 gamerpoints - Choose the patience option all the way through the line in the Carnival.

You've been Cole-slaw-tered! - 20 gamerpoints - Die 10 times in a row through the floating stairs.

Only when he stops breathing - 10 gamerpoints - Set the Dialog Volume slider to zero.

Gold rush - 30 gamerpoints - Complete five Gold Challenges.

Shields up - 30 gamerpoints - Complete a Gold- or Silver-tier Challenge while countering at least 25 times.