Yeah, prior to AoS, Nox Mages were terrifying. Poison was much more dangerous back then, because it did a lot more damage (4-5 ticks of DP and you were dead) and was a lot more difficult to cure (Cleanse By Fire/Cleansing Winds didn't exist, Vampire Form didn't exist, Enhance Potions didn't exist, Pots didn't stack, Arch Cure didn't have an increased cure chance, bandages slipped on even 1 point of damage, and spells took longer to cast and so were more susceptible to interrupts). The only thing capable of inflicting Lethal Poison (Lvl 5) back then, were Silver Serpents, and it was basically a death sentence, 4 ticks you were dead, and it was almost impossible to cure.
A single Nox Mage could easily turn the tide of a battle over a champ spawn. If you dropped DP Poison Fields on someone's boat, they were screwed.