[MunchkinMan]

Originally Posted by Brf

Then the enhancer would disappear from the mate?

Mate is a card which represents a duplicate of another Monster in play. It doesn't have any cards played on it directly, so if you use Illusion to replace the Mate, the Enhancer on the original Monster goes nowhere, but now there is no Mate of the original, just a new Monster added by Illusion. If you play Illusion on the original Monster, any and all Monster Enhancers on the original go, and the Mate duplicates the new Monster introduced by Illusion.