Xagok, High Chieftain of the Cragmaw

Shapechanger. Xagok can use his action to polymorph into a Large dragon-humanoid hybrid or into a Huge dragon, or back into his true form, which is humanoid. His statistics, other than his size, are the same in each form. Any equipment he is wearing or carrying isn't transformed. He reverts to his true form if he dies.

Ice Walk (Dragon or Hybrid Form Only). Xagok can move across and climb icy surfaces without needing to make an ability check. Additionally, difficult terrain composed of ice or snow doesn't cost him extra movement.

Legendary Resistance (3/day). If Xagok fails a saving throw, he can choose to succeed instead.

Multiattack. Xagok uses his Frightful Presence if he is in dragon form. He then makes three attacks, only one of which can be his bite.

Bite (Dragon or Hybrid From Only). Melee Weapon Attack: +11 to hit, reach 5 ft. or reach 10 ft. in dragon form, one target. Hit: 17 (2d10 + 6) piercing damage plus 9 (2d8) cold damage.

Claw (Dragon or Hybrid From Only). Melee Weapon Attack: +11 to hit, reach 5 ft., one target. Hit: 13 (2d6 + 6) slashing damage.

Spear (Humanoid or Hybrid Form Only). Melee or Ranged Weapon Attack: +11 to hit, reach 5 ft. or range 20/60 ft., one target. Hit: 13 (2d6 + 6) piercing damage, or 15 (2d6 + 6) piercing damage if used with two hands to make a melee attack.

Tail (Dragon Form Only). Melee Weapon Attack: +11 to hit, reach 15 ft., one target. Hit: 15 (2d8 + 6) bludgeoning damage.

Frightful Presence (Dragon Form Only). Each creature of the Xagok's choice that is within 120 feet of Xagok and aware of him 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 Xagok's frightful presence for the next 24 hours.

Cold Breath (Dragon Form Only, Recharge 5-6). Xagok exhales an icy blast in a 60-foot cone. Each creature in that area must make a DC 19 Constitution saving throw, taking 54 (12d8) cold damage on a failed save, or half as much damage on a successful one.

Xagok 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. Xagok regains spent legendary actions at the start of his turn.

Move. Xagok moves up to his speed without provoking opportunity attacks.
Polymorph. Xagok polymorphs into his dragon or hybrid form, or reverts back to his humanoid form.
Tail Attack. Xagok makes a tail attack.
Rampage (Costs 2 Actions). Xagok makes a spear attack against each creature within 5 feet of him.
Wing Attack (Dragon Form Only, Costs 2 Actions). Xagok beats his wins. Each creature within 10 feet of Xagok must succeed on a DC 19 Dexterity saving throw or take 13 (2d6 + 6) bludgeoning damage and be knocked prone. Xagok can then fly up to half his flying speed.