Grunt Birthday Party Skull
Skull Effect:When you get a headshot on an enemy Grunt, they will explode into confetti, and you’ll hear children cheer, “Yay!” in excitement.
Campaign Scoring Multiplier: None
Skull Location:The Grunt Birthday Party Skull is located near the middle of the second level, Crowsnest.
The Skull is located in the area just before where you team up with the Arbiter (it’s the piping area where you see Drones buzzing in and out of various of pipes).
Just before you jump down the pipe to meet up with the Arbiter, stop at the ledge, and look directly below you. Along the wall that you drop down, there is a small ledge with a green arrow pointing backwards. Jump onto this ledge (rather than all the way down), and you will end up on the edge of a secret room. The Skull is at the end of this room.