You are a Humanoid.

You are Medium.

Your walking speed is 30 feet, and you have a swimming speed equal to half of your walking speed.

You have claws that you can use to make unarmed strikes. When you hit with them, the strike deals 1d6 + your Strength modifier slashing damage, instead of the bludgeoning damage normal for an unarmed strike.

You can hold your breath for up to 1 hour.

You can see in dim light within 60 feet of you as if it were bright light, and in darkness as if it were dim light. You discern colors in that darkness only as shades of gray.

Your shell provides you a base AC of 18 (your Dexterity modifier doesn’t affect this number). You can’t wear light, medium, or heavy armor, but if you are using a shield, you can apply the shield’s bonus as normal.

You have a dragon turtle ancestor, granting you a special magical affinity. Choose one kind of dragon turtle from the Dragon Turtle Ancestry table. This determines the damage type for your other traits, as shown in the table.

Dragon Turtle Ancestry

When you take the Attack action on your turn, you can replace one of your attacks with an exhalation of magical energy in a 15-foot cone. Each creature in that area must make a Dexterity saving throw (DC = 8 + your Constitution modifier + your proficiency bonus). On a failed save, the creature takes 1d10 damage of the type associated with your Chromatic Ancestry. On a successful save, it takes half as much damage. This damage increases by 1d10 when you reach 5th level (2d10), 11th level (3d10), and 17th level (4d10).

You can use your Breath Weapon a number of times equal to your proficiency bonus, and you regain all expended uses when you finish a long rest.

You have resistance to fire damage.

Starting at 5th level, as an action, you can channel your boiling energy by radiating intense heat. Until the start of your next turn, whenever a creature starts its turn within 5 feet of you, it must make a Constitution saving throw (DC = 8 + your Constitution modifier + your proficiency bonus) or take 2d8 fire damage. Being underwater doesn't grant resistance against this damage. Once you use this trait, you can’t do so again until you finish a long rest.

Starting at 11th level, as a reaction, you can make lightning temporarily surround you to protect yourself. You gain 10 temporary hit points until the start of its next turn. Until all these temporary hit points are gone, any creature that touches you or hits you with a melee attack takes 1d12 lightning damage. Once you use this trait, you can’t do so again until you finish a long rest.