Starving Venom Dragon

Convoke, Flying
When Starving Venom Dragon enters the battlefield, it gets +X/+X where X is the highest
power among creatures your opponent(s) control.
During your precombat main step, you may have Starving Venom Dragon become a copy of a creature
your opponent controls until the end step.
If Starving Venom Dragon is destroyed, destroy all creatures.