Where is the sumo slammer card in Area 51 of Ben 10 Protector of Earth on psp?

In Ben 10: Protector of Earth for PSP, the Sumo Slammer card in Area 51 can be found after you defeat the boss in the level. Once you've defeated the boss, head to the right side of the area. You'll need to use Ben's abilities to navigate through platforms to find the card hidden behind some crates. Be sure to explore thoroughly, as some areas may require specific transformations to access.