Dragon, Oceanus Adult (CR 13)

Huge Dragon (Extraplanar)
Alignment: Always neutral good
Initiative: +0; Senses: blindsense 60 ft., darkvision120 ft., low-light vision, and keen senses
Languages: Celestial, Draconic, and Aquan

AC: 30 (-2 size, +22 natural), touch 8, flat-footed 30
Hit Dice: 22d12+132 (275 hp); DR: 10/magic
Fort +18, Ref +12, Will +15
Speed: 40 ft., fly 150 ft. (poor), swim 90 ft.
Space: 20 ft./10 ft.
Base Attack +22; Grapple +41
Attack: 1 bite +31, 2 claws +26, 2 wings +26, 1 tail slap +26, 1 crush +26
Damage: 1 bite 2d8+11, 2 claws 2d6+5, 2 wings 1d8, 1 tail slap 2d6, 1 crush 2d8
Special Attacks/Actions: Breath weapon 12d8 (27)
Abilities: Str 33, Dex 10, Con 21, Int 14, Wis 15, Cha 14
Special Qualities: Amphibious, immune to electricity, detect evil, control water, smite evil, Frightful Presence: DC 26, SR 26
Feats: #Feats: 8
Skills: Skill points: 50
Advancement: 23-24 HD (Huge)
Climate/Terrain: Any land and underground (Any Upper Plane)
Organization: Solitary (1 dragon, any age), clutch (1d4+1 wyrmlings, very young, young, juvenile, or young adults), family (pair of mature adults and 1d4+1 offspring)
Treasure/Possessions: Triple Standard

Source: Draconomicon

Breath Weapon (Su): An Oceanus dragon has two types of breath weapon, a line of lightning or a cone of tranquility gas. Creatures within the cone must succeed on a Will save or become dazed for 1d6 rounds plus 1 round per age category of the dragon. Both breath weapons function normally underwater.

Smite Evil (Su): Once per day an Oceanus dragon can make a normal attack to deal extra damage equal to its HD total against an evil foe.

Spell-Like Abilities: At will - detect evil; 3/day - control water, holy smite, water breathing; 1/day - control winds, dispel evil, holy word.

Extraplanar Subtype

A subtype applied to any creature when it is on a plane other than its native plane. A creature that travels the planes can gain or lose this subtype as it goes from plane to plane. This book assumes that encounters with creatures take place on the Material Plane, and every creature whose native plane is not the Material Plane has the extraplanar subtype (but would not have when on its home plane). An extraplanar creatures usually has a home plane mentioned in its description. These home planes are taken from the Great Wheel cosmology of the D&D game (see Chapter 5 of the Dungeon Master's Guide). If your campaign uses a different cosmology, you will need to assign different home planes to extraplanar creatures.

Creatures not labeled as extraplanar are natives of the Material Plane, and they gain the extraplanar subtype if they leave the Material Plane. No creature has the extraplanar subtype when it is on a transitive plane; the transitive planes in the D&D cosmology are the Astral Plane, the Ethereal Plane, and the Plane of Shadow.