Darksteel Reactor [Darksteel] Kaito " are blocking or being

" are blocking or being blocked by the same creature

Set: Fallout Type: Artifact Creature — Construct Rarity: Rare Cost: {X}{X} Assaultron Invader enters the battlefield with X +1/+1 counters on it

Set: Hour of Devastation Prerelease Promos Type: Legendary Creature — God Rarity: Mythic Cost: {3}{B}{R} Whenever a creature with a -1/-1 counter on it dies

Set: Portal Second Age Type: Sorcery Rarity: Rare Cost: {4}{R}{R} Each player sacrifices four lands

I'm never taking them off

Darksteel Reactor [Darksteel] Kaito " are blocking or beingSet: Darksteel Type: Artifact Rarity: Rare Cost: {4} 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.