I would try to get Umbreon into the game early on so you can start confusing your opponent's Pokemon, but if you can't get it out early, I would recommend putting it on your bench, attaching three energy cards to it, and waiting for your opponent to put a Pokemon with a lot of energy cards attached to it in the active Pokemon spot, I would then move Umbreon into that active Pokemon spot and use Shadow Shutdown until Umbreon is knocked out or retreated, I would hope to get lucky and flip 2 coins so my opponent would have to discard all their energy on that active Pokemon
Early results are light, but Fabled events are already trickling in over the pre-release weekend
Sure, they might be better or worse at different times, but they're seldom going to be outright bad to see
It's easy to start but contains enough strategy and depth to keep experienced players interested
A Retreat Cost of 2 isnt good, but its kinda ridiculous compared to things like Donphan getting Retreat 4