Marina Vendrell's Grimoire — Duskmourn: House of Horror #64

When Marina Vendrell's Grimoire enters, if you cast it, draw five cards.

You have no maximum hand size and don't lose the game for having 0 or less life.

Whenever you gain life, draw that many cards.

Whenever you lose life, discard that many cards. Then if you have no cards in hand, you lose the game.