Roaring Furnace // Steaming Sauna

(You may cast either half. That door unlocks on the battlefield. As a sorcery, you may pay the mana cost of a locked door to unlock it.)

Roaring Furnace

When you unlock this door, this Room deals damage equal to the number of cards in your hand to target creature an opponent controls.

Steaming Sauna

You have no maximum hand size.

At the beginning of your end step, draw a card.