20 more HP and this thing might have been at least playable.
Though maybe not. Synthesis is...meh, I guess. It's light acceleration at the cost of your turn. This card's main purpose would probably come from Revenge blast, which does 30 plus 30 more for each prize card given up. This provides an interesting option for taking a last minute prize against any pokemon on the field, including an EX. Fighting resistance is okay, but both it and its fire weakness are fairly irrelevant due to the low hit points. Grass isn't the best type however, as Feraligatr is the only pokemon even remotely important that suffers weakness to grass.
I don't think this card has much of a place in the meta. If it weren't for the fact it surrendered two prizes, I could see some people using this with Mewtwo EX I guess. Due to the two prize loss though, I think this card's only purpose would be for an RDL styled closer, taking one or two prizes at the end of the game for 150-180 damage.
Even considering the poor type and lack of synergy and grass partners, Shaymin's fragility is a huge problem. 110 HP is bad in our current format, nevermind when EXs come out, and nevermind that this is an EX. Doing 120 damage is not that hard, so giving up two prizes to such a likely scenario isn't good. Enough decks tech dragons and that probably isn't going to change anytime in the near future unless EX completely replace them, which doesn't help Shaymin's chances much. Eviolite helps a little, but a single pluspower is all Zekrom needs for the knockout, and fire weakness condemns it against Reshiram anyway. Revenge Seed is alright, and is one of the few attacks that can OHKO EX pokemon. If you're down a prize, it can put the game in your favor. Unfortunately, short of teching a Shaymin UL or some sort of acceleration, it will take you two turns to power Shaymin EX up. It may have a place in Emboar variants for that reason but the fact this card gives up two prizes really knocks down what is already a situational tech, and no card should give up two prizes for helping "some of the time".
I'm giving Shaymin a 3/10.
Worth Two Prizes? NO