Special for my Brave Roy?

Galeforce or Draconic Aura or Moonbow. It also depends on his iv, what's his iv? Also he comes with Galeforce as default, what's wrong with that, you didn't spend 20k feathers for it so what's the problem?

Or if I misunderstood and your talking about the special/Sacred seal then +Spd 3 or +3 Atk should work.

Galeforce!

l'd go with Galeforce, and if you want to guarantee trigger it consistently then Deathblow and Swordbreaker would work great with it.