[Fate]

Plus, a swarm of low level mages casting low level spells once your research is done (almost) never hurts.

For low level fire mages mid-late game (probably the weakest mage imaginable) you could:

* use them for a sontaneous summon lesser fire elemental/will-o-wisp (situational)

* spam combustion/blindness/evocs/rage/bonds of fire - while not worth doing extra research or specifically buying mages for the purpose, a few more attacks always help.

* decoys. They work fine as this, if a little expensive, though they count as mages for the spells that care about that (plus they have above-human MR).

* Turn your fire gems into low level items (fire bolas on indie commanders? ring of fire/fire swords for your thugs?)

None of these are really worth buying them, but remember you buy them for the research. Anything else they manage to do before becoming cannon fodder is just extra.