Gargantua is not an earth elemental; they are two different creatures.
And did we just completely ignore the game's world? Hobbits and leprechauns were never mentioned in Heroes of Might and Magic V or Dark Messiah.
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This actually leaves room for imagination when creating the Faceless Ones. They are decent fighters, and at the time of Heroes of Might and Magic VI, they hadn't been destroyed yet.
Why did we ignore it? After all, the events take place 400 years before Heroes of Might and Magic V; who knows who lived with the elves back then, and the mages also seemed to have beastmen living with them, replacing the orcs, and there were no gremlins back then. They were created to repair golems and gargoyles.
But instead of whom should they be, if they are going to be included, let them replace the Sorceresses. There's no need to touch the Hydras and Black Dragons.
Демократия есть одурачивание народа при помощи народа ради блага народа.(Уайльд Оскар)