Midra, Frenzied Flame Lord

As long as you have one or fewer cards in hand
Midra has vigilance and haste. Whenever
Midra attacks, look at the top six cards of your library. You may exile a legendary creature
card from among them. Put the rest on the bottom of your library in a random order.
Until end of turn, you may cast the exiled card
without paying its mana cost.