energy is a card that you attach to Pokèmon to get them to attack. There are lots of different sorts of energy. Some are called basic energy which are normal energy cards which only give out one of one type. Here are all of them:
There are other
energy cards called special energy cards. You can only have 4 of these in your deak. Here are some of them:
Double Colourless Energy
Double Dragon Energy
Double Aqua Energy
Double Magma Energy
This card is Rayquaza-EX. Look at the good energys to attach, the energy cards needed in the attack cost and The different thing about dragon type.
Dragon type is different from the other types because dragon Pokémon need two different types of basic energy in their attack costs.
Colorless energy symbols in attack costs mean you can attach any sort of energy and other symbols (let's say fire for instance) mean you can only attach an energy of their type.