Eragon

To unlock "Fury Mode", Go to the ingame pause menu, and hold all triggers down, and enter X, X, B.

There are 16 Secret Eggs to be found in the game, one for each level of the game. Whenever you find a secret egg, it will unlock one of the following items. And the unlockables are unlocked in the following order, regardless of which egg you've found first.

Effect - Code

Bonus Level: Throne Room Find Secret Egg # 16
Commentary - Art Direction Find Secret Egg # 03
Commentary - Birth of a Game Find Secret Egg # 04
Commentary - Design Find Secret Egg # 02
Commentary - Edward John Speleers Find Secret Egg # 01
Commentary - Evolution of Games Find Secret Egg # 14
Commentary - Garrett Hedlund Find Secret Egg # 13
Commentary - Orchestra Find Secret Egg # 06
Commentary - Robert Carlyle Find Secret Egg # 11
Commentary - Saphira Find Secret Egg # 07
Commentary - Sienna Guillory Find Secret Egg # 08
Commentary - Sound Effects Find Secret Egg # 12
Concept Art - Beor & Varden Find Secret Egg # 15
Concept Art - Characters Find Secret Egg # 09
Concept Art - Gil’ead Find Secret Egg # 10
Concept Art - Spine, Carvahall & Daret Find Secret Egg # 05

This level is an endurance match where you you will battle round after round of Galbatorix's men in front of his throne.

Effect - Code

Throne Room - Find all of the hidden eggs in the game at any difficulty.