You show up as Guilty to all investigations.
Any Watcher targeting a player who was killed will see you as the killer, regardless of who actually killed that player.
All actions targeting you succeed even if they shouldn't.
Each night, you may use one of these abilities which are one-shot unless otherwise specified:
Hellfire - You may target a player to kill with fire, as if you were an Arsonist priming then immediately igniting your target. This ability can be used an unlimited number of times.
Hellfrost - You may target a player to freeze. The frozen player will be announced to be frozen, but will count as removed from the game the next Day and Night (they count as dead for wincon purposes, but for all other purposes the player doesn't exist at all). This ability can be used an unlimited number of times.
Soulbond - You may target two players to link them in one neighborhood and make all actions affecting one affect the other as well (this can be called soulbonding)
Possess - You may target a player to learn what night actions the player has if any and gain the 1-shot ability to control the use of their night actions.
Demonic Surge - You may use two other abilities tonight.
When you die during the Night, the next phase is a Demon's Shadow phase where night actions happen as normal except that standard kill actions will always fail. When you die during any other phase, the phase after the next Night phase is a Demon's Shadow phase.
You win when all other players are dead or nothing can prevent this from happening.
Mod Note: The alignment-role split of this role is named Demon Lord regardless if it is the alignment or role. The Demon Lord alignment only has the Serial Killer wincon (without the factional kill), all of the abilities are part of the Demon Lord role.
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I missed post #6666