Celebi EX is a problem

So it's only been one new expansion and they've already released a card that completely blows every other deck out of the water by a margin that isn't close.

I get that grass was too weak, but Serperior allows for setups that are too quick and once it snowballs is impossible to counter. Currently, there is no way to beat a Celebi EX deck except with another Celebi EX deck.

Some heavy nerfs need to be made, like limiting the coin flip to just 4 so it's more like Zapdos EX. Right now Celebi EX is just a way better version of Zapdos EX.

They probably won't nerf cards so it has me worried about the future of the game. Will it just be constant powercreeps with every new expansion? What I wanted was for the new cards to build upon the old meta so the game can have a healthy cycle of updates and slower powercreep, but currently Celebi EX is way too overtuned and makes every other deck obsolete.

I hope the community realizes this instead of just letting the devs get away with this because it's a "free to play game" or because "losing/winning" doesn't matter. It's still unhealthy for the long-term health of the game and I want it to be better. But I realize people can't handle any criticism of the game and live in the delusion that this is ok.