Anserath, the Honking Chaos

If Anserath would be reduced to 0 hit points, its current hit point total instead resets to 310 hit points, it recharges its Cachonkphonical Madness, it regains any expended uses of Legendary Resistance, and it gains resistance to bludgeoning, piercing and slashing damage for 1 hour. Additionally, Anserath can now use the options in the "Mythic Actions" section for 1 hour. Award a party an additional 50,000 XP (100,000 XP total) for defeating the Anserath after its Berserk Honkwakening activates.

Anserath ignores difficult terrain, and magical effects can't reduce its speed or cause it to be restrained. It can spend 5 feet of movement to escape from nonmagical restraints or being grappled.

If Anserath fails a saving throw, it can choose to succeed instead.

Anserath has advantage on saving throws against spells and other magical effects.

Anserath can take one reaction on every turn in combat.

Anserath has advantage on saving throws against being blinded, deafened, stunned, or knocked unconscious.

Anserath attacks with its Webbed Claws twice, then can attack each target in reach with A Thousand Beaks or cast a spell.

Melee Weapon Attack: +15 to hit, reach 15 ft., one target. Hit: 19 (2d10 + 8) magical piercing damage. Once per turn, Anserath can force a hit target to make a DC 23 Strength saving throw, pulling the target within 5 feet of Anserath's space on a failed save.

Melee Weapon Attack: +15 to hit, reach 5ft., one target. Hit: 18 (4d4 + 8) magical piercing damage and the target becomes grappled (DC 23 to escape).

Each of Anserath's heads honks horribly and the demon chooses up to six points it can see within 150 feet. Each of these points magically bursts into a 15-foot radius honksplosion and everything in the area is affected by one of the following effects. A target in the area ofmore than one burst is affected only once. Roll a d6:

Anserath makes an attack.

Each of Anserath's heads honks disturbingly. Every creature within 20 feet of Anserath that can hear it makes a DC 23 Wisdom saving throw. On a failed save, a creature takes 13 (2d12) psychic damage and becomes frightened. A frightened creature repeats the saving throw at the end of each of its turns, ending the effect on a success or taking another 6 (1d12) psychic damage on a failed save. A creature that goes to 0 hit points while frightened in this way receives a long-term madness (see Chapter 8 of the Dungeon Master's Guide).

Each creature grappled by Anserath takes 14 (4d6) magical piercing damage, becomes restrained while grappled and makes a DC 23 Constitution saving throw. On a failed save, a creature develops a random goose mutation (see Fowlish Mutations for the table and for how to heal from it). After three of these mutations, a creature turns into a demogoose*. A creature affected by the web limbs spell counts as already having one of these mutations.

Anserath moves up to its speed in a straight line. When Anserath enters the area of a creature while doing so, it attacks the creature with A Thousand Beaks.

Anserath casts the confusion spell with its Spellcasting.