Gargantuan dragon, neutral
Armor Class 20 (natural armor)
Hit Points 341 (22d20 + 110)
Speed 20 ft., swim 40 ft.
Saving Throws Dex +6, Con +11, Wis +7
Damage Resistances fire
Senses darkvision 120 ft., passive Perception 11
Languages Aquan, Draconic
Challenge 17 (18,000 XP)
Amphibious. The dragon turtle can breathe air and water.
Multiattack. The dragon turtle 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: +13 to hit, reach 15 ft., one target. Hit: 26 (3d12 + 7) piercing damage.
Claw. Melee Weapon Attack: +13 to hit, reach 10 ft., one target. Hit: 16 (2d8 + 7) slashing damage.
Tail. Melee Weapon Attack: +13 to hit, reach 15 ft., one target. Hit: 26 (3d12 + 7) 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.
Steam Breath (Recharge 5–6). The dragon turtle exhales scalding steam in a 60-foot cone. Each creature in that area must make a DC 18 Constitution saving throw, taking 52 (15d6) fire damage on a failed save, or half as much damage on a successful one. Being underwater doesn’t grant resistance against this damage.