f25a08f0_Secrets_for_PSP___GameRankings__Unlockable
[How to Unlock] Boomerang Kuwanger [Unlockable] 
After going up the spikey platform, wait for the platform to slow down, jump on top of the tiny platform before it breaks and jump to the left.
Mega Man Maverick Hunter X Cheats, Codes, and Secrets for PSP - GameRankings