What can be said about balors that hasn’t already been said? Pit fiends may get a lot of press, but if you have enough firepower, they’ll listen to reason. Balors won’t. Balors can summon a CR 19 vrolikai with 100% accuracy…y’know, just because. And it was a balor by another name that brought down Gandalf in the Mines of Moria.
Since learning the shadow demon Fusziarch’s true name, a balor summons him almost exclusively. A lord among his own kind (CR 17), with eldritch oracle powers boosting his own umbral abilities, Fusziarch will promise adventurers almost anything if they can disrupt the balor’s control. He’s so desperate, he might even keep his word.
A balor’s power approaches nascent demon lord status. Ambitious, he begins to search out a realm to own and a portfolio to claim. His choice of the former arouses a dangerous qlippoth; his choice of the latter could wake an ancestral nemesis of the taiga giant pantheon long thought deceased.
Balors lead the hordes of the Abyss to battle against the legions of the Hells. When a balor lord routes the demons in his charge through the Demiplane of Mirrors and the halls of the Morrowmaze, a whole mortal world trembles in fear.
—Pathfinder Bestiary 58-59