Learn more fighting abilities
A lot of life chargers are required for this trick. You have to fight the mutants to learn different types of fighting moves. Fight one over and over again by going back into the room. Sometimes the best thing to do is to allow a mutant hurt you first. A "bing" sound will indicated that you have learned a new fighting ability. Do not forget to save the moves.
Avoiding fights
You do not have to fight all enemies. You can run past them, or you could get across pits with enemies by jumping in the pit, running to the other side, and jumping out.
Play as Alien
To play as an alien enter L, R, L, R, and Z at the title screen.
Play as President Weller
To play as President Weller enter: L, R, L, R, and start at the title screen.
More Fighting Abilities
Find any spot with a savegame area near one of those yellow things that guys keep coming out of, fight, get hit, or grapple, and everytime you hear a ding you have learned a new skill. Also this is great for upping your offense and defense and will work with a lot of powerups too.
Extra Mode
Beat the game under Ultimate. Then at the Title screen, press L, R, L, R, A.
Learn more fighting abilities
A lot of life chargers are required for this trick. You have to fight the mutants to learn different types of fighting moves. Fight one over and over again by going back into the room. Sometimes the best thing to do is to allow a mutant hurt you first. A "bing" sound will indicated that you have learned a new fighting ability. Do not forget to save the moves.