GUNVALKYRIE Cheats
GUNVALKYRIE cheat codes, tricks, hints, and walk throughs.
Unlock Challenge Mode
To unlock Challenge Mode, which allows you to go through and select any level you've played, beat the game once (a feat which is more difficult than it sounds).Unlock Kelly-Level 3
In order to unlock the third version of the Kelly, collect all of the Halley Cores in the game.
