The Forty Thieves are a band of bandits who regularly submit to more powerful villains. They are soldiers who only feature prominently in the second Disney Vs Non Disney Villains War.
Disney Vs Non Disney Villains
Disney Vs Non Disney Villains - Part Two
By the time of the second war, the newly crowned Ruber delegates command of the Forty Thieves to Oroku Saki and, by extension, Hun. However, Sa'Luk returns and bests Hun in combat, taking control of the thieves once more. The thuggish leader also purchases some powerful Talismans.
It is this latter action that brings the thieves in conflict with another group, the Dark Hand. The Dark Hand is in possession of the other Talismans, Talismans Sa'Luk wants for himself. The thieves ambush the Dark Hand, only to be thoroughly crushed by the magically enhanced Dark Hand enforcers. As a result, Sa'Luk loses his remaining Talismans.