Sounds like one of Tidus's overdrives, to me, but I don't think that's considered an ability. Anyways, here's my reasoning.

Persistence is key - In order to gain Tidus's overdrives, you have to meet use requirements. Persistence in using the overdrive is key to gaining more powerful overdrives.

Accuracy is vital - You have to be accurate to hit R1 at the appropriate time to accomplish the overdrive.

Quickest Rival - Doesn't really fit. nevermind. xD