Bonnacon (also Bonacon)
AC 7 
Atk 1 headbutt (1d6)
Special: Caustic Spray - Cone 30' long x 20' wide
The Bonnacon resembles a great bull, but with a shaggy mane like a horse. Its horns curl backwards, making them all but useless for goring in defense.
When startled or attacked, a Bonnacon will turn and attempt to flee, releasing a putrid spray of liquid caustic manure. This spray will cause 3d4 points of acid damage, and if a victim fails their saving throw they will be incapacitated by the stench for 1d10 rounds.