R Energy.

R Energy can be attached only to a Pokémon that has Dark or Rocket's in its name. While in play, R Energy provides 2 Darkness Energy. (Doesn't count as a basic Energy card.) If the Pokémon R Energy is attached to attacks, the attack does 10 more damage to the Active Pokémon (before applying Weakness and Resistance). When your turn ends, discard R Energy.