Cloudstone Curio [Ravnica: City of Guilds] Apocalypse −5: Artifacts you control become

−5: Artifacts you control become artifact creatures with base power and toughness 5/5 until end of turn

If Cosmic Horror is destroyed this way

The worst part isn't the pain

Pyromaster deals 1 damage to target player or planeswalker and 1 damage to up to one target creature that player or that planeswalker's controller controls

Cloudstone Curio [Ravnica: City of Guilds] Apocalypse −5: Artifacts you control becomeSet: Ravnica: City of Guilds Type: Artifact Rarity: Rare Cost: {3} Whenever a nonartifact permanent enters the battlefield under your control, you may return another permanent you control that shares a permanent type with it to its owner's hand. It *wants* to remain a mystery, banishing the curious in favor of less inquisitive company.