Seath, Crystal Scholar

Lord over wizards, flying, attune 6
When Seath, Crystal Scholar enters the battlefield, place a crystal counter on target
artifact you control. Seath, Crystal Scholar has indestructible as long as you control this counter.
Consumed{2}{u}{u}{r}: Tap all creatures. They
don't untap on their next untap step. Activate
only if you sacrifice 3 artifacts.