Plot

It would be worth adding a point about the fact that after the Reckoning on Enroth, an army of Krags came from that fiery world (HoMM4), settled there, and formed a new Inferno (roughly equal in strength to the Inferno that Lucifer created on the orders of Xenofex). And the world, I repeat, is not Xeen, but Enroth. And also, what can the Mongols do against the same Inferno, Necropolis, or Powder Brotherhood?
Vori is not a continent, but a large island surrounded by ice (and also covered with snow and ice on the edges).

Added 2 minutes ago
Let it be better not an entrance to "Atlantis - the world of water," but an entrance to "Atlantis - one of the areas of the Sphere of Water."