Nyarlathotep, Crawling Chaos

Shadow, Menace, Shroud
Madness {b}{b}{b}, pay half your life (rounded up)
All cards you own have Madness pay half your life (rounded up).
Whenever an opponent would discard a card,
they exile that card instead.
"It is the end. They have come down through the
gloaming from the stars."-H.P. Lovecraft