>>37868856It's a GX attack, you can only use one once per game. Also, having your opponent return their Benched Pokemon back into their hand as an attack effect isn't that uncommon and not that game-breaking (unlike having them shuffle their Active Pokemon back into the deck or return it to their hand, those CAN win the game for you under certain circumstances).
It's Ability is much more fun to use, you can bypass the standard Froakie-Frogadier-Greninja evolution route or the more-common Froakie-Rare Candy-Greninja route and making Greninja-GX (or any other card) the only card in your hand can be easy to do.
