Another Fine Myth by Robert Asprin

All I could think of was Garkin, so I pictured the two faces side by side.

“Now move the new face over mine . . . and melt away or build up the necessary features. Like clay . . . just keep that in the back of your mind and open your eyes.”

I looked, and was disappointed.

“It didn’t work!”

“Sure it did.”

He was looking in the dark mirror which he had fished from his belt pouch.

“But you haven’t changed!”

“Yes I have. You can’t see it because you cast the spell. It’s an illusion, and since your mind knows the truth, it isn’t fooled, but anyone else will be. Garkin, huh? Well, it’ll do for now.”

His identification of the new face took me aback.

“You can really see Garkin’s face?”

“Sure, want to look?”

He offered the mirror and grinned. It was a bad joke. One of the first things we discovered about his dubious status in this world was that while he could see himself in mirrors, nobody from our world could. At least I couldn’t.

I could now hear the sounds of the rider coming.

“Aahz, are you sure….”

“Trust me, kid. There’s nothing to worry about.”

I was worried. The rider was in view now. He was a tall muscular man with the look of a warrior about him. This was reinforced by the massive war unicorn he was riding, laden with weapons and armor.

“Hey, Aahz. Shouldn’t we.:..”

“Relax, kid. Watch this.”

He stepped forward, raising his arm.

“Hello, stranger! How far to the next town?”

The man veered his mount toward us. He half raised his arm in greeting, then suddenly stiffened. Heaving forward, he squinted at Aahz, then drew back in terror. “By the Gods! A demon!”