Sahaquiel, The 8th Angel

When Sahaquiel, The 8th Angel enters the battlefield: Put 5 Momentum Counters on it.
During your upkeep:
Remove 1 Momentum Counter.
When Sahaquiel, The 8th Angel has no
Momentum Counters:
Sacrifice Sahaquiel, The 8th Angel,
Target Player's nonbasic Lands and nonlegendary
Artifacts are destroyed.
(Only activate this as a sorcery).