Summoning Chamber

You light three black candles and place them on the altar. Holding aloft your scroll of ancient forbidden unspeakable evil, you speak the name aloud...

"Kermithulhu"

There is a sound like a thunderclap, and a fearsome demon appears over the altar in a burst of fire and brimstone.

"Behold, mortal!" it bellows. "You have summoned the great and mighty Bub Bobmur, and I shall grant you your heart's desire!"

"Wow, really? That's great!" you exclaim. "...Wait, though. Did you say your name was Bub Bobmur?"

"That is correct, mortal."

"That's weird," you reply, "because that's not what I said to the altar at all. I said 'Kermithulhu'.

"Hmm," ponders the demon. "We must've gotten some sort of crossed signal. Oh well. Never mind, then."

The demon vanishes in a puff of greasy black smoke.