"Rats and jackals feast in his swath, but even they will not walk with him."
—Mangara

Duskmourn: House of Horror Commander

Kaervek the Merciless

Whenever an opponent casts a spell, Kaervek the Merciless deals damage equal to that spell's mana value to any target.

Whenever an opponent casts a spell, Kaervek the Merciless deals damage equal to that spell's converted mana cost to any target.

Whenever an opponent casts a spell, Kaervek the Merciless deals damage to target creature or player equal to that spell's converted mana cost.

Whenever an opponent plays a spell, Kaervek the Merciless deals damage to target creature or player equal to that spell's converted mana cost.