A new supporter card was leaked today, and it's seriously good.
Ninja Boy – Trainer
Search your deck for a Basic Pokemon and switch it with 1 of your Basic Pokemon in play. (Any cards attached to that Pokemon, damage counters, Special Conditions, and effects on it are now on the new Pokemon.) Shuffle the first Basic Pokemon into your deck.
You may play only 1 Supporter card per turn (before your attack).
This is a game changer, as it allows you to switch into something else and then treat that Pokemon as if it were already in play. This card has loads of potential, and will likely be used quite a bit in many decks.