Hastur, the Moon Lord

Indestructible, Flying, Haste
When you cast Hastur, the Moon Lord, you may
look at target player's hand. Choose a card from
it and exile that card. You may cast that card and
use mana as if it were mana of any color to cast it.
You have no maximum hand size. At any time,
if you have less than seven cards in your hand,
you lose half your life, rounded up.