If the Pokemon Darkness Energy is attached to does damage with an attack (after applying Weakness and Resistance), the attack does 10 more damage. At the end of every turn, put 1 damage counter on the Pokemon Darkness Energy is attached to, unless it's D or has Dark in its name. Darkness Energy provides D Energy. (Doesn't count as a basic Energy card.)
Near Mint - $4.50
Near Mint Reverse Holofoil - $16.00
Lightly Played - $4.30
Lightly Played Reverse Holofoil - $15.20
Moderately Played - $3.80
Moderately Played Reverse Holofoil - $13.60
Heavily Played - $3.40
Heavily Played Reverse Holofoil - $12.00
Damaged - $3.20
Damaged Reverse Holofoil - $11.20