Gonna go with Str/Ath.  Using the Great Cat template from the Exalted Core, that gives me a dice pool of 9 (Str 6 for the cat, 2 Athletics +1 for the stunt.)  Taking my mote back.<br/><br/>ETA: Dice came up with 3 successes, but all of those are 10s, and I don't know how to set the dicebot so 10 comes up as 2 successes instead of 1.  So it's really 6 on the grapple check.