I was about to check this one out quickly, but apparently the new patch messed something up with the magic paths of recruitables, so I can't give very meaningful feedback atm.
The first thing I thought about when reading your description though was: Earth/fire mage = Magma eruption.
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Praeterea censeo, contributoribus magnae auctoritatis e Foro Shrapnelsi frequenter in exsilium eiectis, eos qui verum auxilium petunt melius hoc situ adiuvari posse.