Aang, the Last Airbender

Defender, reach
{r/w}: Aang, the Last Airbender gets +2/+0 or
+0/+2 until end of turn.
{g/u}, {t}: Exile target legendary creature card from
a graveyard. Draw a card.
{w}{u}{r}{g}: Until end of turn, Aang, the Last Airbender becomes a Human Monk Avatar, gets
+3/+3, loses defender and gains double strike,
flying and hexproof. Activate this ability only if
you've been dealt damage this turn.