:: video games cheat and cheat codes ::                                            

Sony PSP - Archer Maclean's Mercury cheats

Select stage
Pick two player mode. Type to initials: hg?
Go back to the main menu. Start a new single palyer game.
Go to the world selection screen. Hold L + R and press Select.
Hold L + R and press Select again to lock all levels.

Unlock bonus stages 
Reach first places on all high score boards in every stages in a world.