Each night, the Horseman of Death may doom a player. The Horseman marks the player, and they will die at the end of the following night.

Dooming a player is an immediate effect. Players doomed by the Horseman of Death will die at the end of the next night (this is not an attack). When the Horseman of Death attempts to doom another Horseman, it fails: the two Horsemen unite, joining a shared channel. Doomed players are informed that they have been doomed, but not which Horseman doomed them. Doomed players can be doomed again by the same or a different Horseman. Dooming and its accompanying effect persist even if the Horseman of Death dies, but immediately disappear when no Horsemen remain. When all remaining Horsemen are united and all remaining players doomed, Doomsday is unleashed: the Horseman of Death turns into an Apocalyptic Horseman, with the ability to attack a player each night. The Horsemen win when everyone else is dead.