Despite being flashy and a 5th level spell, Magic Mirror serves very little function in the game. Faerie Dragons are well-protected by its effects, but by the time you have a hero with the mana and a Mage guild upgraded to the highest level, there are likely at least a few spells in your spellbook you'll more want to cast in combat. Arguably this spell would not have been overpowered even if it could be mass cast like slow, prayer, or curse. And because only one troop stack can be targeted for protection, it will almost never be the ideal choice to cast in combat.
20-40% chance to reflect an enemy spell. Or in other words... 100% chance that you cannot cast any spell on an enemy, and 100% chance that an enemy can hit your units with his spells. 100% useless spell even if it was level 1 with 10% of the spell points cost --172.26.0.4 18:04, 27 October 2019 (UTC)