Battalion Wars cheats and cheat codes for Gamecube

Bonus Mission 1: Reach 85% completion on the 1st Campaign.
Bonus Mission 2: Reach 85% completion on the 2nd Campaign.
Bonus Mission 3: Reach 85% completion on the 3rd Campaign.
Bonus Mission 4: Reach 90% completion on the 4th Campaign.

Level 6: You get the heavy tank and the gunship:
Press X, X, A, B, Y, X, Z