Cornugon

(From Planescape: Monstrous Compendium Appendix I  - 1994):

Cornugons, the elite fighting force in Baator, form terrifying armies up to 2,000 strong. Only pit fiends may lead these hideous fighting forces into battle. Pit fiends and gelugons prize cornugons as personal guardians and try to obtain them as personal retainers. The Dark Eight have 106 cornugons in their retinue.

Cornugon armies usually form only in the lowest layers of Baator. In the upper layers, individual comugons serve as generals to vast armies of lesser baatezu. This duty is desirable for its rapid advancement, second only to guardian duty among the Dark Eight.

The cornugons are greater baatezu, and as such enjoy a certain prestige. Of all the baatezu, the cornugons and hamatula advance most rapidly.

With several successful campaigns to their credit, heroic comugons receive promotions to the upper layer of Baator, where they command vast, gruesome legions of baatezu. From there, distinguished action leads to promotion to gelugons, the ruthless inhabitants of the frigid layer of Caina.

Although powerful and cunning, the cornugons display treachery in their ranks least often of all baatezu, due to their militaristic nature. Their loyalty makes them an unusual asset. It is said that the 106 cornugons that guard the Dark Eight are completely loyal and would give their lives in defense of the council, behavior nearly unheard of in Baator. Whether this is due to genuine loyalty or fear of the pit fiends is unknown, but seldom in the history of the Dark Eight has a cornugon guardian displayed traitorous behavior.

Combat: Cornugons are fearless fighters, rarely retreating from combat even against overwhelming odds. They have 18/00 Strength (+6 damage adjustment). Cornugons attack with their tail for 1d3 points of damage, creating a wound that bleeds 1 point per round until treated. In addition, they attack with either claws (1d4 points of damage) and bite (1d4+1 points of damage), or with a barbed whip (1d6 points of damage and save vs. paralyzation or be stunned for 1d4 rounds).

In addition to the magical abilities inherent in all baatezu, cornugons can use the spell-like powers detect magic, ESP, lightning bolt (3 times per day), produce flame, pyrotechnics and wall of fire (once per day). They can attempt to gate in the following: 2 to 12 barbazu (50% chance, once per day), 2 to 16 abishai (35% chance, once per day), and 1 to 3 additional cornugons (20% chance, once per day).

All comugons radiate a fear aura in a 5-foot radius. Anyone entering the radius must save vs. rod, staff, or wand or flee in terror for 1d6 melee rounds. Cornugons regenerate 2 hit points per melee round.

(From Monster Manual (2014):  

Horned devils are lazy to the point of belligerence and reluctant to put themselves in harm’s way. Moreover, they hate and fear any creature stronger than themselves. When they are sufficiently provoked or antagonized, the fury of these fiends can be terrifying.

A malebranche stands as tall as an ogre and is sheathed in scales as tough as iron. The flying infantry of the hellish legions, horned devils follow orders to the letter. Their huge wings and sweeping horns create an intimidating presence as they drop from the sky and strike with deadly forks and lashing tails.