Well, I just looked through my PS Underground demo disc (the one with Ape Escape on it) and it does indeed use the L3/R3 buttons (crouching, diving in the water, using the net in the water, and hiding). Some other games on the disc that use the L3/R3 buttons (or just one of them) are Omega Boost, Twisted Metal 4, Tomb Raider: The Last Revelation, Supercross Circuit (crappy motorcycle game, R3 does the same thing as circle), and Ace Combat 3. The disc also has Umjammer Lammy on it, perhaps I should try it out

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