Type (TCG)
Elemental types play as large a part in the Pokémon TCG as they do in the Game Boy games. Both Pokémon and Energy cards can be one or more of these types. Similarly, a Pokémon can and probably will have a Weakness and Resistance to other types.
Unlike in the Game Boy adventures, there are only 9 types.
Also, unlike the Game Boy adventures, when a Pokémon attacks, the type of damage it does is based on the Pokémon's elemental type and not the type of Energy the attack requires. For example, a Psychic Pokémon will always do "Psychic damage", and even if the Energy types required for the attack are "Water Energy" it won't do "Water damage". Likewise, Pokémon in the TCG also can't do an 1.5 times damage if their attack and type are of the same Elements.
Because of the limited number of types, many of the 17 types found in the Game Boy adventures have been combined into one of the TCG types. For example, Poison, Bug and Grass types in the Game Boy adventures are instead combined into the Grass type in the TCG. However, in keeping with Pokémon tradition, the Weakness and Resistance of certain Pokémon are similar to their weaknesses in the Game Boy adventures. For example, even though Grimer is a Grass type in the TCG, it is weak is to Psychic, much like in the Game Boy adventures.
Another difference between the Game Boy adventures and the TCG is how damage is calculated according to Weakness and Resistance. If a Pokémon has a weakness to another Pokémon's type, the damage done is doubled. If a Pokémon has a resistance to another Pokémon's type, that damage is reduced by 30 damage points, rather than being halved.
