Secret Gamer Pic
Complete the game on Insane difficulty to unlock a secret gamer picture. It has the Red Gear’s Symbol behind Marcus Fenix.
Contributed By: Mikeaspike
Secret Gamer Pic #2
Unlock the "Seriously ..." achievement by getting 10,000 kills in ranked multiplayer matches to get that respective GamerPic
Contributed By: nismojoe
Easter Eggs
Gears Cereal!
On Act 5, when you are on the train and press the very first button you see, the berserker will magically appear. It will be expressed through a cut scene where it busts through a couple of box, and a lot of objects "explode" from these boxes.
If you manage to make it around the berserker, go to the very last car on the train, (the one the berserker appears on,) You will find a cereal box, I believe to be called "Gears Crunch." On the backside of these boxes, there is a fictional prize you could win (which happens to be a small fluffy pillow!)
Contributed By: AbbeyRd