Future expansions.

T.E.
Basic Units:
Minotaur
Duelist
Beast

Elite Units:
Assassin
Air Elemental
Air Priest

Champions:
Hydra

Added 9 minutes ago
Krygane (arrived on Ashan from space):
Basic Units:
Imp - Fiend
Gog - Fire Gog
Ifrit - Efreet

Elite Units:
Demon Warrior
Volcano Spirit - Lava Spirit
Infector - Hell Infector (They have an unusual ability - 100 Infectors, or 50 Hell Infectors, will turn every captured city into a Hive)

Champions:
Archdemon - Devil

Added 4 minutes ago
Elemental City (2 basic units, but 4 elite units):
(but it doesn't combine with other cities - the champion is a Leprechaun. Here, it's a large man in a green suit with a sword in his hand. When he dies, he jumps into a hat. He teleports by jumping into the hat and appearing in another place. +2 Luck - to everyone on the battlefield.)
Basic Units:

Light Servant - Lesser Spark (additional upgrade, to Champion - Light Elemental)
Dragon Priest - Elemental Mage

Elite Units:
Air Elemental
Earth Elemental
Water Elemental
Fire Elemental

Champion:
Leprechaun