Alert. Kezef has +5 to initiative checks and can never be surprised.
Flawless Tracker. Kezef The Chaos Hound can designate a single creature as his prey and thereafter will never fail to catch the creature's trail. Kezef knows the direction and distance to his quarry even across different planes of existence.
Fetid. Any creature that starts its turn within 10ft of Kezef must succeed on a DC18 Constitution saving throw or be poisoned until the start of the creature's next turn. All non-magical fires within 60 feet of the Chaos Hound are extinguished.
Corrosion. Any non-magical weapon made of metal that hits Kezef corrodes. After dealing damage the weapon takes a permanent and cumulative -1 penalty to damage rolls. If its penalty drops to -5 the weapon is destroyed. Nonmagical ammunition made of metal that hits Kezef is destroyed after dealing damage. A creature that touches Kezef or hits it with a melee attack while within 5 feet of it takes 2d12 acid damage.,,
Multiattack. Kezef makes three attacks: one with his bite and two with his claws.
Bite. Melee weapon attack: +16 to hit reach 10ft. one target. Hit: 31 (4d10 + 9) piercing damage plus 11 (2d10) acid damage.
Claw. Melee weapon attack: +16 to hit reach 5ft. one target. Hit: 22 (3d8 + 9) slashing damage.
Terrifying Howl. Kezef emits a terrifying howl that causes panic and confusion. All creatures within 30ft feet that can hear him must make a DC 20 Charisma saving throw. On a failure a creature suffers the effects of a confusion spell for 2d6 rounds. On a success a creature must make a DC 20 Charisma saving throw or suffer the effects of a fear spell. A creature can repeat the saving throw at the end of each of its turns ending the effect on itself on a success. If a creature succeeds on both saving throws it is immune to Kezef's Terrifying Howl for the next 24 hours.
Acid Breath (Recharge 5-6). Kezef exhales acid in a 30 foot cone. Each creature in the cone must make a DC 20 Dexterity saving throw taking 54 (12d8) acid damage on a failed save or half as much damage on a successful one. A creature that fails the saving throw by 5 or more is coated in acid taking 54 (54d8) acid damage at the beginning of their next turn.
Magic Resistance. Kezef has advantage on saving throws against spells and other magical effects.
Magic Weapons. Kezef's weapon attacks are magical.
Legendary Resistance (3/Day). If Kezef fails a saving throw he can choose to succeed instead.
Innate Spellcasting. Kezef's innate spellcasting ability is Charisma (spell save DC 22 +15 to hit with spell attacks). He can innately cast the following spells requiring no material components:
At will: crown of madness, dissonant whispers, etherealness, fly, greater invisibility
3/day: confusion, plane shift
Kezef can take 3 legendary actions choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature's turn. Kezef regains spent legendary actions at the start of his turn.
Sow Discord. Kezef casts crown of madness or dissonant whispers makes a Wisdom (Perception) check or a Wisdom (Survival) check.
Frenzy. Kezef makes a claw attack at every creature within 5ft.
Planar Jaunt. Kezef shifts into the ethereal plane hunting his prey. While in the ethereal plane Kezef can move without provoking attacks of opportunity. At the end of this movement Kezef returns from the ethereal plane and may make a bite attack with advantage against a creature within range.
Mastiffs are impressive hounds prized by humanoids for their loyalty and keen senses. Mastiffs can be trained as guard dogs, hunting dogs, and war dogs. Halflings and other Small humanoids ride them as mounts.
Keen Hearing and Smell: The mastiff has advantage on Wisdom (Perception) checks that rely on hearing or smell.
Other-worldly sight: The mastiff can see Invisible creatures and objects out to a range of 60 feet.,,
Bite: Melee Weapon Attack: +3 to hit, reach 5 ft., one target. Hit: 4 (1d6 + 1) piercing damage. If the target is a creature, it must succeed on a DC 11 Strength saving throw or be knocked prone.