What are Dark Metal Energy Cards?
Dark Metal Energy Cards are Special Energy Cards that are used in the Pokémon Trading Card Game (TCG). They were first introduced in 2004 with the launch of the EX Team Rocket expansion set and last seen in the EX Holon Phantoms set of 2006.
See also: What are Special Energy Cards?
Dark Metal Energy cards provide Darkness and Metal Energy but only one at a time. There have been two different designs for these cards but they both include the Metal Energy symbol over the Darkness Symbol. (Scroll to bottom for timeline and gallery of all cards released to date).
In the Pokémon TCG, a player can only use an Attack Move if the specified number of Energy are attached. This specified number generally includes one or more Energy that corresponds to the Pokémon type, and / or a number of Colorless Energy. Dark Metal Energy Cards provide one Darkness or one Metal Energy.
Dark Metal Energy Cards Text:
The text on the cards is roughly the same but with a minor change to the text. Listed below are two different texts seen on the cards in order of release.
2004 EX Team Rocket Returns release
‘Attach Dark Metal Energy to 1 of your Pokémon. While in play, Dark Metal Energy provides 
2005 EX Holon Phantoms release
‘Attach Dark Metal Energy to 1 of your Pokémon. While in play, Dark Metal Energy provides
Timeline of Dark Metal Energy Cards:
To date these cards have been included in 2 different expansion sets. They have always been part of the set and have card numbers. The cards released are listed in order of release. (scroll to bottom for gallery view).
EX Team Rocket Returns
Released 2004
Card Number –
94/109
EX Holon Phantoms
Released 2006
Card Number –
97/110
Gallery
