There are two items (I am not counting the Fossils as, though they do have their own abilities, they are just the awkward things you evolve prehistoric Pokemon from), one which could be useful, one which is just annoying: Energy Sticker allows you to attach a basic energy from your discard pile on coin flip
They also typically feature special illustrations of the Pokmon
Magicians Souls While Magicians Souls is itself a Spellcaster, its so good for Spellcaster decks that I couldnt possibly make a list of support cards and not mention this one
UR Ultra Rare (Duelist Saga Version) Pot of Duality X SPELL Excavate the top 3 cards of your Deck, add 1 of them to your hand, also, after that, shuffle the rest back into your Deck
The first card on the list is the hands-down best Sword of X&Y, Sword of Feast and Famine
You can then apply this knowledge to build your game