[Norfleet]

You said Illithids were involved: The vfx for Mind Burn, Paralyze, etc, is the same as the one for Mind BLast. Did you hear a loud WHOOOOOOSH! noise as this happened? That's your aforementioned 38 illithids mindbLasting your troops, causing temporarily paralysis. It's not the spell "Mind Burn", although some of his commanders may have cast both Mind Burn and Enslave Mind, as these are astral spells which R'lyeh is good with.