Ice Beam would be an amazing coverage move for Keldeo.
These, off the top of my head, are the current OU pokes that resist Keldeo's STAB options:
-Gyarados
-Jellicent
-Tentacruel
-Starmie
-Dragonite
-Salamence
-Latios
-Latias
-Celebi
-Venusaur
That's a total of 10 pokes. Keep in mind that...