RTF is a global modification that replaces all towns in the game.

Are demons degrading? For me, a demon is a somewhat intelligent creature, and a giant worm is just an animal (that chases after a Saret faster than it can think).

We are talking about the worm from Heroes 6. The Fire Worm, not the one from Dark Messiah. True, this one also didn't demonstrate any signs of intelligence, and I don't know why Zobyr considers it the pinnacle of evolution, because it seems to be just a cool demon of one of the princes. Demons are essentially divided into legions of princes, and each has its own specifics, depending on the prince. One specializes in imps and their matrons, another has a lot of bulls, the third is about madness, etc. Nevertheless, it is known that the initial form of a demon is an imp, and they return to it when they are killed. In addition, some demons were mortal and became demons after death. For example, Zana was reborn as a succubus; this is a feature of this species, they do not become imps. Apparently, demons can evolve, arise from the souls of mortal sinners, reproduce, and simply be created artificially. In general, this corresponds to their infinite number, but not all demons are intelligent. Hounds, nightmares, and most likely the worm are not intelligent. Nevertheless, an imp is partially intelligent and can become an unintelligent hellhound. And theoretically, it can even rise to the position of Kha-Belekh. This is what this race is like.

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Remember: each individual imp could theoretically become a new ruler of Shio...