This is not a "bug" per se, but arguably a "game balance" issue resulting from the recent introduction of the "sons of arsena" unit in the dragon city. First of all, though, thanks much for developing and continually upgrading such an awesome mod. I rarely go back to play "normal" civ, FFH is so awesome!
Anyway, my current strategy I just developed is to use a civ or religion with relatively early access to a level 3 spell caster hero (e.g. combine Elohim with Council of Esus to get two of them!) and only upgrade the spell caster with "mind." Then, with those units well-protected by other units, I go to the dragon city, and start "dominating" the new "sons of arsena/inferno" units. Sometimes the domination does not work and I lose the ability, but I just re-upgrade to "mind III" again when that happens. The game I played last night, I ended up with an army of about 15-20 of the sons of arsena units which I dominated from the dragon city (which are themselves level 3 spell casters, some of which I also eventually upgraded to "mind III" to help dominate even more units), each of which can summon fire elementals (and use other level III spells) every turn -- I can easily use such an army to steam-roll over any other civ. (I play at immortal difficulty, which means that there are a lot of such units generated.)
Even though this strategy is quite fun, it leads to a rather imbalanced game (and a good way to get around the limit on only having four archmages, well before you can even build archmages). It would probably be worth tweaking the game to make such a strategy more difficult or impossible (e.g. giving the sons of arsena the "loyalty" promotion so they cannot be converted, or making it more difficult to convert them, or adding barbarian assassins into the mix at the dragon city and having the barbs aggressive about using them against spell-casters, or just having the sons of arsena more aggressive about sending fire elementals against stacks of units with spell casters, or . . .).
Thanks again for such a cool mod! (When are you going to have it ready for Civ 5?

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