Duskmourn: House of Horror

Enduring Courage | Enchantment Creature | Dog Glimmer | Whenever another creature you control enters, it gets +2/+0 and gains haste until end of turn. When Enduring Courage dies, if it was a creature, return it to the battlefield under its owner's control. It's an enchantment. (It's not a creature.) | Yigit Koroglu

Fear of Missing Out | Enchantment Creature | Nightmare | When Fear of Missing Out enters, discard a card, then draw a card. Delirium — Whenever Fear of Missing Out attacks for the first time each turn, if there are four or more card types among cards in your graveyard, untap target creature. After this phase, there is an additional combat phase. | John Stanko

Leyline of Resonance | Enchantment | | If Leyline of Resonance is in your opening hand, you may begin the game with it on the battlefield. Whenever you cast an instant or sorcery spell that targets only a single creature you control, copy that spell. You may choose new targets for the copy. | Sergey Glushakov

Leyline of Mutation | Enchantment | | If Leyline of Mutation is in your opening hand, you may begin the game with it on the battlefield. You may pay {W}{U}{B}{R}{G} rather than pay the mana cost for spells that you cast. | Sergey Glushakov

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