Yveltal/Meowstic Deck

Ok so this deck is sort of a combination between the destruction rush and mystic typhoon theme decks. It is my first deck so please keep in mind that I am definitely not an expert at this. This also means that any tips to make this deck better are greatly appreciated! Thanks!
2 Yveltal
2 Inkay
1 Malamar
3 Sandile
2 Krokorok
1 Krookodile
1 Druddigon
3 Espurr
2 Meowstic
2 Duskull
2 Dusclops
2 Evosoda
1 Great Ball
1 Hard Charm
2 Max Revive
2 Potion
2 Professor's Letter
1 Muscle Band
1 Professor Sycamore
2 Poke Center Lady
1 Shauna
2 Tierno
1 Shadow Circle
12 Dark Energy
9 Psychic Energy

Too many Pokemon and too much Energy. You need to pick and choose some Pokemon and lessen the amount of Energy. Prof Sycamore should be increades in number and potion should be discarded already. If you have any EXs that fit in this deck, use them.