Harbinger

Flying, indestructible
When you cast Harbinger, gain control of target opponent during that player's next turn. After
that turn, that player takes an extra turn.
{2}{b}, Reveal Harbinger from your hand: Target creature you control gets +2/+2, is legendary,
and is named Harbinger until end of turn.
Activate this ability only once per turn.
"Assuming direct control."