Damage done to Pokémon Energy is attached to is reduced by 10 (after applying Weakness and Resistance). If the Pokémon Energy is attached to isn't , whenever it damages a Pokémon, reduce that damage by 10 (before applying Weakness and Resistance). Energy provides Energy. (Doesn't count as a basic Energy card.)
Important Card Rulings & Erratas
- Metal Energy reduces damage only from attacks. This means Pokémon Powers like Dark Crobat's Surprise Bite and Elekid's Playful Punch should not have their damage reduced by a Pokémon with Metal Energy attached to them.
- Double damage reduction (2x10=20) for self-damage from non-Metal Pokémon is legit.