Dragon Turtle (CR 9)

Huge Dragon (Aquatic)
Alignment: Usually neutral
Initiative: +0; Senses: darkvision 60 ft., low-light vision, scent, Listen +16, and Spot +18
Languages: Aquan, Draconic, and Common

AC: 25 (-2 size, +17 natural), touch 8, flat-footed 25
Hit Dice: 12d12+60 (138 hp)
Fort +13, Ref +8, Will +9
Speed: 20 ft., swim 30 ft.
Space: 15 ft./10 ft.
Base Attack +12; Grapple +28
Attack: Bite +18 melee
Full Attack: Bite +18 melee and 2 claws +13 melee
Damage: Bite 4d6+8, claw 2d8+4
Special Attacks/Actions: Breath weapon, snatch, capsize
Abilities: Str 27, Dex 10, Con 21, Int 12, Wis 13, Cha 12
Special Qualities: immunity to fire, sleep and paralysis
Feats: Blind-fight; Cleave; Improved Bull Rush; Power Attack; Snatch
Skills: Diplomacy +3, Hide +7*, Intimidate +16, Listen +16, Search +16, Sense Motive +16, Spot +18, Survival +16 (+128 following tracks), and Swim +21
Advancement: 13-24 HD (Huge); 25-36 HD (Gargantuan)
Climate/Terrain: Temperate aquatic
Organization: Solitary
Treasure/Possessions: Triple standard

Source: Monster Manual

Dragon turtles are fierce fighters and generally attack any creature that threatens their territory or looks like a potential meal.

Breath Weapon (Su): Cloud of superheated steam 20 feet high, 25 feet wide, and 50 feet long, every 1d4 rounds; damage 20d6, Reflex half DC 21; effective both on the surface and underwater.

Snatch (Ex): A dragon turtle that hits with a bite attack attempts to start a grapple as a free action without provoking an attack of opportunity. If it gets a hold on a creature three or more sizes smaller, it seizes the creature with its mouth and automatically deals bite damage each round. If it does not move and takes no other action in combat, it deals double bite damage to the snatched creature. A snatched creature gets no saving throw against the dragon turtle's breath weapon.

The dragon turtle can drop a creature it has snatched as a free action or use a standard action to fling it aside. A flung creature travels 60 feet and takes 6d6 points of damage.

Capsize (Ex): A submerged dragon turtle that surfaces under a boat or ship less than 20 feet long capsizes the vessel 95% of the time. It has a 50% chance to capsize a vessel from 20 to 60 feet long and a 20% chance to capsize one over 60 feet long.

Skills: Dragon turtles receive a +8 racial bonus to Hide checks when submerged.

Aquatic Subtype

Creatures with the aquatic subtype always have swim speeds and thus can move in water without making Swim checks. An aquatic creature can breathe underwater. It cannot also breathe air unless it has the amphibious special quality.