Rush 'n Attack Codes -

Alternate Sound FX
At the main menu, press , , , , , , , , , to unlock alternate sound effects. A meow sound will confirm the code was entered correctly.

Achievements
Complete the following tasks to unlock achievements and their alloted gamerscore:

Bravery (15) - Use only your knife to beat the Harbor Level.
Fair Fight (10) - Reach the mortar without defeating any unarmed soldier in Missile Base.
Good Start (10) - Complete the Missile Base.
Knife Master (20) - Complete all levels using only your knife and no powerups.
Mad Marine (30) - Rescue the POWs twice.
Not Bad (10) - Get a score of 50,000 or more.
Reflexes (15) - Complete the Missile Base without dying.
Stamina (15) - Complete the Bridge Level.
Stealth (15) - Complete Missile Base, deafting less than 18 enemies.
Teamwork (20) - Score 200,000 or more playing an Xbox Live co-op match.
True Marine (20) - Rescue the POWs in less than 10 minutes.
Victory (20) - Beat the Enemy Prison Camp.