+reactor (2)
Indestructible (Effects that say "destroy" don't destroy this artifact.)
At the beginning of your upkeep, you may put a charge counter on Darksteel Reactor.
When Darksteel Reactor has twenty or more charge counters on it, you win the game.
Whenever Dragonspark Reactor or another artifact you control enters, put a charge counter on Dragonspark Reactor.
, Sacrifice Dragonspark Reactor: It deals damage equal to the number of charge counters on it to target player and that much damage to up to one target creature.
Gatherer works better in the Companion app!