Marit Lage, the Slumbering

Suspend 10 - {b}{b}
Whenever Marit Lage, the Slumbering enters the battlefield or attacks, choose one —
• Destroy each blue or red permanent.
• Destroy each planeswalker.
• Destroy each other snow permanent.
Flying, indestructible (Damage and effects that say "destroy" don't destroy this creature.)