Darkness Energy
If the Pokémon 
Energy is attached to attacks, the attack does 10 more damage to the Active Pokémon (before applying Weakness and Resistance). Ignore this effect unless the Attacking Pokémon is or has Dark in its name. Energy provides Energy. (Doesn't count as a basic Energy card.)
Energy is attached to attacks, the attack does 10 more damage to the Active Pokémon (before applying Weakness and Resistance). Ignore this effect unless the Attacking Pokémon is or has Dark in its name. Energy provides Energy. (Doesn't count as a basic Energy card.)