the developers, starting with Heroes of Might and Magic V, tried to introduce them into the Sylvan faction, but something always prevented them... and then suddenly the idea came to make the dragon non-flying, and as a result, we got only one flying unit for the entire army, and that was at the first level (fairies). So they decided to add the phoenix. Besides, either the Humans or the Light Dragons will have the Light Child in tandem with Blindness – they didn't want to duplicate the unit, and in the end, they wouldn't throw out the Ent either.

Added 1 minute ago
Manticoras will not be with the Orcs:smile29: - either as a Tier 3 unit or as a neutral unit.