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Sly owns the darkest night in this costume. Cloaked in shadow, he's a tireless force for justice... and picking pockets!
― In-game description[src]

Ultimate Sly is a skin available for Sly Cooper to wear in Sly Cooper: Thieves in Time. It can be obtained by collecting 15 Sly Masks. It puts Sly into a red and black super hero costume, reminiscent of Batman and Robin from DC Comics.

Like most other Sly Masks awards, it is for visual purpose only and makes no changes to gameplay.