Duskmourn: House of Horror

Charred Foyer // Warped Space | Enchantment // Enchantment | Room // Room | (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.) At the beginning of your upkeep, exile the top card of your library. You may play that card this turn. // (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.) Once each turn, you may pay {0} rather than pay the mana cost for a spell you cast from exile. | Andrew Mar

Glassworks // Shattered Yard | Enchantment // Enchantment | Room // Room | (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.) When you unlock this door, this Room deals 4 damage to target creature an opponent controls. // (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.) At the beginning of your end step, this Room deals 1 damage to each opponent. | Sergey Glushakov

Ticket Booth // Tunnel of Hate | Enchantment // Enchantment | Room // Room | (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.) When you unlock this door, manifest dread. // (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.) Whenever you attack, target attacking creature gains double strike until end of turn. | Marco Gorlei

Roaring Furnace // Steaming Sauna | Enchantment // Enchantment | Room // Room | (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.) When you unlock this door, this Room deals damage equal to the number of cards in your hand to target creature an opponent controls. // (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.) You have no maximum hand size. At the beginning of your end step, draw a card. | Miklós Ligeti

Smoky Lounge // Misty Salon | Enchantment // Enchantment | Room // Room | (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.) At the beginning of your first main phase, add {R}{R}. Spend this mana only to cast Room spells and unlock doors. // (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.) When you unlock this door, create an X/X blue Spirit creature token with flying, where X is the number of unlocked doors among Rooms you control. | Marco Gorlei