You have a fair point on the Oath moves. Serperior has perfect stats to use the moves, since it is fast, yet still somewhat bulky. In doubles/triples you could pair it with another starter, and let it use dual screens as well as the oath moves. The set could look something like:
Serperior @ Light Clay/Leftovers
252 HP/252 Spe/4 SpAtt
Grass Oath
Light Screen
Reflect
Glare






I don't know what claiming it does, but I claimed it.
