Finishing Moves?

Umm so I have 2 finishing moves.. explosion and aerial finish.. but ever since I got the other one, explosion is not going off on my finishing move.. does only 1 work at a time? Does that mean I should take off one or the other?

EDIT: I just got rumbling rose.. I'm guessing by it's description it activates all finishing moves? But Hero's crest seems really good too by having finishing attacks be based on number of air combos.. which should I use?

Explosion only works with ground combos. It won't go off in the air when you have aerial finish.

I'd go with Rumbling Rose, by the way.

Later in the game, you'll learn moves called Guard Break and Finishing Leap. Those are also both finishing moves, and if you have the Rumbling Rose or the ability Finishing Plus then you can perform more than one in a row. You only have one aerial finisher normally. If you are in Valor Form, you have two aerial finishers and can perform them both with the above item/ability.