Diabellstar, Seeker of Sin

This card costs {1} less to cast for each legendary artifact card in your graveyard. Legendary artifacts you control have: "{t}, sacrifice this artifact: Add 1 mana of any color to your mana pool."

Whenever a legendary artifact is sacrificed, put X +1/+1 counters on this card, where X is the sacrificed card's mana cost.

{t}, {w}{u}{b}{r}{g}: Search your library for a legendary artifact, cast it by removing counters from this card equal to twice its mana cost, then shuffle.