Mephistus

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[muh-FIST-uhs]
Demesne: Lies
Alignment: NE
Portfolio: Deception, Planning, Illusion, Pride, Evil
Appearance: Mephistus has no known definite appearance. For that matter, no one ever knows if it is actually physically present. Any who believe they are certain of either are fools, but Mephistus delights in false certainty as much as suspicion. Though it is able to assume the form of any living or non living thing, in truth, it may just be a roiling, vaguely human-shaped fog of shadow and mist, or its true form is hidden behind the persistent veil.
Behavior: Even other fiends dislike working with Mephistus, for it is forever scheming and enacting numerous plots at once. One can never know its true intentions; Mephistus is as likely to tell the truth as lie, or even equivocate, and is just as likely to deceive out of vindictiveness or desire for entertainment. One also never knows for certain if one is actually talking to who they think they are, for it also enjoys impersonation just for the sake of creating distrust.
Philosophy: Trust no one. Everyone thinks most of him or herself and cares nothing for you. Tell no truths but those that will earn you trust, and learn whatever you can from others that will gain you power. But most of all, you must master the art of deception in word and action, for living by lies is the only way to survive when everyone else seeks power over you. There is no reason to suffer when you can craft for yourself a world that is completely in your control.
Influence: Mephistus's influence is great both in breadth and depth. Unlike the deviance of Belphegor or Baphomet, Mephistus's demesne is subtle and stronger in human nature. Especially in a world in which Beiatus's influence creates so much guilt and shame, Mephistus can delight in twisting desire for self-preservation to spreading of lies and suspicion.
Favored Fiends: Pride and Doubt.