Celebi EX


Up until the Mythical Island expansion, Grass was basically ruled by Venusaur EX and its bulky-offense play-style. This made Grass a great type, but there were times when it was a bit lacking in raw power. And then along came Celebi EX, and its ability to throw out nuclear coin-tosses!
Celebi EX is a very interesting card, to say the least. It's heavily RNG based, but that RNG can be quickly turned in its favor with additional energy. This makes Celebi EX extremely energy-hungry, but the dividends paid out for the investment can be downright staggering, as with enough energy it's possible for it to semi-reliably take down literally any card in the game in a single hit. This is a card that you are going to kind of want to build around, but it also can't hurt to just throw one into a Grass deck focused on another strategy as an alternate win-condition.
Celebi EX + SerperiorGo to Deck

Celebi EX thrives on energy, so getting Lilligant out early to generate energy, and then having Serperior on the bench (you only need one, they don't stack) before Celebi EX hits the field can easily result in 10+ coin flips in just a few turns, which is more than enough to KO literally anything in the game more than 50% of the time on average.
Celebi EX + Exeggutor EXGo to Deck

An example of a Celibi EX/Exeggutor EX deck. Exeggutor EX makes a FANTASTIC wall with high damage and an extremely low energy cost attached. Getting it on the field early can make it easy to get a lot of energy on Celebi EX. The rest of the cards are purely here to try to get what you want on the field and support the overall strategy.