Antimony (Avatar)

Legendary Resistance (2/Day). If Antimony fails a saving throw, it can choose to succeed instead.

Evasion. If Antimony is subjected to an effect that allows it to make a Dexterity saving throw to take only half damage, Antimony instead takes no damage if it succeeds on the saving throw, and only half damage if it fails.

Prancer. Antimony can move 15 feet if it succeeds a dexterity saving throw. No matter how much movement it has used.

Poisonous Hide. Antimony's hide is poisonous to the touch, contact with antimony with bare skin will result in 1d4 poison damage. 

Quicksilver .  For every time Antimony lands a hit with its Hoove attack, one of its Hooves is ignited in silver fire and it gains ten feet of movement. Once all four legs are ignited antimony will focus on a far away place, up to 10 miles away and prepare to run there. It will spend one whole turn focusing, to be stopped antimony  must be subjected to some effect that would cause it to move (shoving, dissonant whispers spell etc.) If antimony is not stopped he dashes to the new location leaving destruction in his wake. Creatures within 200 ft of Antimony will take 6d10 force and 6d10 thunder damage both where it stands and where is it going.

Reins of fear.  The reins on Antimony are made from fear. To grab the reins and ride the beast you must succeed a  dexterity saving throw, DC 17, or be subjected to a bite attack. As well as a wisdom saving throw, DC 17, or be inflicted with insanity. 

Multiattack. Antimony can use its Frightful Presence. It then makes three attacks: one with its hooves and two with its bite.

Bite. Melee Weapon Attack: +9 to hit, reach 10 ft., one target. Hit: 14 (2d10 + 8) piercing damage plus 6 (2d6) necrotic damage. Creatures who are under the influence of Frightful Presence also take 6 (2d6) psychic damage.

Hooves. Melee Weapon Attack: +9 to hit, reach 5 ft., one target. Hit: 10 (2d6 + 8) bludgeoning damage.

Frightful Presence. Each creature of Antimony's choice that is within 120 feet of Antimony and aware of it must succeed on a DC 17 Wisdom saving throw or become frightened for 1 minute. 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's saving throw is successful or the effect ends for it, the creature is immune to Antimony's Frightful Presence for the next 24 hours.

Fire Breath (Recharge 5–6). The dragon exhales fire in a 60-foot cone. Each creature in that area must make a DC 17 Dexterity saving throw, taking 20 ( 10d4) fire damage on a failed save, or half as much damage on a successful one.

Antimony 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. Antimony regains spent legendary actions at the start of its turn.

Trot. Antimony charges at a creature it can see in a straight line up to its movement. it Hits the creature with a Slam. Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 12 (2d10 + 5) bludgeoning damage. If the attack hits the creature must make a strength saving throw DC 14, or be knocked prone.

Back Kick. Melee Weapon Attack: +9 to hit, reach 5 ft., one target. Hit: 10 (2d6 + 8) bludgeoning damage.