Mystery Man

The Mystery Man is an NPC that was added in The Sims: Makin' Magic. He appears on all Magic Town lots, where he sells and buys wands. In addition, Sims can ask him about various aspects of magic.

Outside of Magic Town, he brings the magical starter kit (A Mysterious Package) when Sims move into a new house. He also serves as the "Spellchecker," and may appear to fine Sims who do magic when non-magical Sims are watching (other than the spell's target)

It is possible that his visits inspired the visits of "Mr Humble" in The Sims 2: Freetime.