Aparctica

Breath of antimagic. Aparctica breaths a cone of antimagic, as in the anti-magic field spell, in a 100-foot-cone.

Calming presence. While in the presence of Aparctica people lose the will to cause harm and feel at peace however evil aligned creatures take 4d4 radiant damage a turn.

Multiattack. Aparctica makes three attacks: one with its bite and two with its claws. It can make one tail attack in place of its two claw attacks.

Bite. Melee Weapon Attack: +16 to hit, reach 15 ft., one target. Hit: 35 (3d12 + 9) piercing damage.

Claw. Melee Weapon Attack: +16 to hit, reach 10 ft., one target. Hit: 25 (2d8 + 9) slashing damage.

Tail. Melee Weapon Attack: +16 to hit, reach 15 ft., one target. Hit: 35 (3d12 + 9) bludgeoning damage. If the target is a creature, it must succeed on a DC 20 Strength saving throw or be pushed up to 10 feet away from the dragon turtle and knocked prone.

Aparctica can take 3 legendary actions, It can take only one legendary action at a time and only at the end of another creature’s turn.

Zone of antimagic. It can cast antimagic field at a 9th level spellslot. Which extends the radius to 120 ft. expelling all magic from spells to weapons.

Saving throw. Succeed any saving throw.