Ratchet and Clank 3 Skill Point question

I have the HD collection of Ratchet and Clank for the PS3 and this is concerning Ratchet and Clank 3 Up Your Arsenal. I have got all 30 of the Skill Points from the game and what it says in the Skill Points section but after you have unlocked the cheats it still says there's one thats Unknkown. Anybody any idea what it is or how to get it.

Er wasn't that to do with the double-ended light saber?

Pause and type:Circle, Square, Circle, Square, Up, Down, Left, Left