The Octopod

Flying, Trample

{w}{u}{b}{r}{g}: Search your library for an Octonaut creature, put that card in your hand, then shuffle.

When the Octopod attacks, sea creatures you control gain indestructible until end of turn.

Tap five legendary creatures you control: The Octopod becomes an artifact creature until end of turn.

The Octopod can be your commander.