Originally Posted by Digital
It could be using Synchronoise, which could mean that Fennekin is part Psychic?
That actually makes the most sense!
I think it's too early to call typing though. We can make an estimate, but none will be near accurate. Chimchar didn't learn any Fighting moves until Monferno. Nor did Torchic until Combusken, so it seems more likely the move used was a TM.
Eevee can learn Synchronoise as well, so that may mean Fennekin obtained it via egg move/tutor/TM/etc as well.
I really am hoping for Psychic though. That or Ground seem the most likely, if anything. o: