Lone Savior

Flash, Flying, Double Strike
When Lone Savior enters the battlefield, all creatures with power 3 or less get indestructible
until end of turn. The destroy all creatures.
When Lone Savior dies, exile all creatures that
were destroyed by or dealt damage by Lone Savior.
{3}{w}{r}: Lone Savior deals 1 damage to each
creature with power 4 of greater. Sacrifice Lone
Savior.