Legendary Resistance (3/Day). If the Zillo fails a saving throw, it can choose to succeed instead.

Magic Resistance. The Zillo has advantage on saving throws against spells and other magical effects.

Reflective Carapace. Any time the Zillo is targeted by a magic missile spell, a line spell, or a spell that requires a ranged attack roll, roll a d6. On a 1 to 5, the Zillo is unaffected. On a 6, the Zillo is unaffected, and the effect is reflected back at the caster as though it originated from the Zillo, turning the caster into the target.

Siege Monster. The Zillo deals double damage to objects and structures.

Multiattack. The Zillo can use its Frightful Presence. It then makes five attacks: one with its bite, three with all three claws, and one with its tail. It can use its Swallow instead of its bite.

Bite. Melee Weapon Attack. +20 to hit, Reach 10ft., 1 target. Damage: 44 (4d12 + 20) piercing. . If the target is a creature, it is grappled (escape DC 20). Until this grapple ends, the target is restrained, and the Zillo can't bite another target

Claw. Melee Weapon Attack. +20 to hit, Reach 15ft., 1 target. Damage: 36 (4d8 + 20) bludgeoning.

Tail. Melee Weapon Attack. +20 to hit, Reach 20ft., 1 target. Damage: 32 (4d6 + 20) piercing. . If the target is a creature, it must succeed on a DC 20 Strength saving throw or be knocked prone

Frightful Presence. Each creature of the Zillo choice within 120 feet of it 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, with disadvantage if the Zillo is within line of sight, 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 the Zillo Frightful Presence for the next 24 hours.

Swallow. The Zillo makes one bite attack against a Large or smaller creature it is grappling. If the attack hits, the target takes the bite's damage, the target is swallowed, and the grapple ends. While swallowed, the creature is blinded and restrained, it has total cover against attacks and other effects outside the Zillo, and it takes 56 (16d6) acid damage at the start of each of the Zillo turns. If the Zillo takes 60 damage or more on a single turn from a creature inside it, the Zillo must succeed on a DC 20 Constitution saving throw at the end of that turn or regurgitate all swallowed creatures, which fall prone in a space within 10 feet of the Zillo. If the Zillo dies, a swallowed creature is no longer restrained by it and can escape from the corpse by using 30 feet of movement, exiting prone.

The Zillo 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. They regain spent legendary actions at the start of their turn.

Attack. The Zillo makes one claw attack or tail attack.

Move. The Zillo moves up to half its speed.

Chomp (Costs 2 Actions). The Zillo makes one bite attack or uses its Swallow.

Enter the description for how mythic actions work for your monster here.

Mythic Action Name (Costs # Actions). Enter the description for your mythic action.