Nightmare

Large Fiend

Armor Class 13

Hit Points 68 (8d10+24)

Speed fly +90, walk +60

Challenge 3

STR
18
+4
DEX
14
+2
CON
16
+3
INT
10
+0
WIS
12
+1
CHA
14
+2

Damage Immunities fire

Senses passive Perception 11

Languages understands Abyssal, Common, and Infernal but can't speak

Special Abilities

Evil. The nightmare radiates an Evil aura.

Fiery Hooves. The nightmare sheds bright light in a 10-foot radius and dim light for an additional 10 feet. The nightmare leaves charred hoofprints.

Fire Resistance. The nightmare can grant fire resistance to a rider.

Actions

Hooves. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 11 (2d6 + 4) bludgeoning damage plus 7 (2d6) fire damage. If the horse moves at least 20 feet straight towards the target before the attack the target makes a DC 14 Strength saving throw falling prone on a failure. The nightmare can move through the space of a prone creature as long as it does not end its turn there.

Ethereal Shift (Recharge 5-6). The nightmare and a rider magically pass from the Ethereal Plane to the Material Plane or vice versa.

Source: Level Up Advanced 5e Monstrous Menagerie · OGL/Open