this is a completely new game since the tech tree is now fixed rather than appended to the end after fusion
however there seems to be some balance issues in this new version
I got hit by mobile level 12 units early in the game.
they went for my defenceless cities rather than staying in uncivilized areas (where I can at least tolerate them by not venturing too far from home).
if I happened not to start next to the correct resources there is no way I could have built an equivalent unit to defend myself
I would have had to back up many turns to build those defensive units since I had no hint such a powerful unit was coming
unlike the work in progress version 0.60 which I played through to the end, I now expected too many nasty surprises from raging barbarians with too much advanced technology and did NOT play through this version
make sure the mod leaves a way to turn off raging barbarians and aggressive AI
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UPDATE: the issue is not how strong the barbarians are, but the fact as bezerkers they went directly to attack my defenceless cities.