How to play
This deck relies on the combo of Crobat with Arceus which gives Crobat a passive dealing 30 damage to the active pokemon. Plus, if this is your active pokemon, it can attack for 50 more damage for the cost of only 1 energy. This can lead you to a pretty 80 damage right on your second turn if you were the starting player, which kills most of early stage non-EX pokemon such as Type:null, Charmander, Litten, Pheromosa... even before they possibly evolve ! If you had to start with an Arceus, its really easy to back it off with even Ilima or Leaf (even if you may prefer to keep Leaf for a blocked DrakraiEX)
You may still count on ArceusEX or DarkraiEX as a long-term strategy with their 3energy attack dealing around 100 damage.
In a dreamed scenario, you can deal up to 210 damage in a turn only with your pokemons : ArceusEX on the active spot + 2 Crobat + DrakraiEX Crobats are each dealing 30 damage and DarkraiEX can deal 20 with its passive too, then ArceusEX attacks for 130 !
I played this deck a lot, and it changed with time and the different match-ups encountered.
The surprise part : As you can see this list is running a non-EX arceus. It seems to be a bad card but it is pretty interesting in that particular deck. First of all, it's another Arceus to help assembling the Crobat Arceus combo. It is also a colorless tank with 120hp which is not bad at all according to the fact that it only gives 1 point on dying, being a nonEX card. This can save you some time to build up and it is easy to back thanks to Ilima and Leaf. That is also another reason to play 2 Ilima ! A pretty insane card when played well, that may win you more games than you could imagine !