Dialga EX

Originally, Dialga EX had little real utility in the meta. It wanted so badly to help power up other cards, but the pool was too shallow.... and then Arceus EX happened. The ability to come in early and tank hits while granting Metal Energy is a VERY valuable niche, as it buys time for the deck's real headliner to come online. As more and more cards that can utilize Metal or colorless energy show up, Dialga's value will continue to rise, but for now it's sitting nicely as one of the game's premier supportive EX cards.