The Gorgons emerged en masse, advancing toward our position and intensifying their petrification spells. Despite the protection that their visors afforded, more mercenaries were succumbing to their terrifying effects.
The defensive runes embedded into their visors (and my glasses) weren't totally foolproof. For one thing, magical runes were completely useless unless you fed them mana. The normal spirit arrays and formations often drew power from a tremendous mana generator. Otherwise it wasn't practical lugging around what we informally termed as "spirited engraved gear." We couldn't provide our own equipment with a constant supply of mana 24/7, after all. Or we would end up exhausting ourselves terribly.
They had their uses, like now, for example. But these Gorgons were rank B monsters. They had an enormous amount of mana, and coupled with their potent petrification spells, they could cause the poor mercenaries to run out of mana before long.