Keldeo's Movepool is...well, more garbage than a dozen Garbodor's bodies. Not that the Moves it gets are bad, far from it - the lack of Moves it can actually use is the part where Keldeo is less of a Special-based Terrakion and more of an are-you-on-crack-ion:
-Usable Water STAB - Hydro Pump, Surf, Scald, Aqua Jet
-Usable Fighting STAB - Focus Blast, Secret Sword
-Other Special-based Moves - Icy Wind, Hidden Power, Round (only for Water + Normal's Type-coverage)
-Misc - Calm Mind, Toxic, Swagger, Light Screen, Reflect, Psych Up
Don't bother too much with Physical-Keldeo. Like Special-Terrakion, you'll be wasting time, especially since Electric, Grass, Flying, and Psychic Type Moves are too common to be messing around.