I'd personally go for a magic experiment gone wrong creating driders/spider centaurs and who then take over and give the spiders a more holy position. a few recruitable spiders which are sacred. I think entering giants (giants AGAIN???) would just dilute the still underused spider theme

. MORE SPIDERS!!!! --> ow this chain of events would make this story LA.. of course it could be turned around and be made in EA (would fit dom 3 better even.. more magical in EA fading that out as the ages pass.
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Want a blend of
fantasy and
sci-fi? Try the total conversion
Dominions 3000 mod with a new and fully modded solar system map.
Dragons wanted? Try the
Dragons, Magic Incarnate nation.
New and different undead nation? Try
Souls of Shiar. Including new powerfull holy magic.
In for a whole new sort of game? Then try my scenario map
Gang Wars.