Some say that the 4 Heroes were once the controllers of Vresun, before her death. Eventually, the 4 Heroes had a falling out and have become two splinter factions: One who wishes to regain control of Vresun and another who want to put Vresun out of her misery.
Rumour has it that in reality, there are only 3 Heroes and that one of them wishes to regain his former glory...