Gaspar (CR 10)

Huge Magical Beast (Extraplanar)
Alignment: Always neutral
Initiative: +2 (Dex); Senses: darkvision 60 ft., low-light vision, Listen +9, and Spot +12

AC: 20 (+2 Dex, -2 size, +10 natural), touch 12, flat-footed 18
Hit Dice: 14d10+112 (189 hp)
Fort +17, Ref +11, Will +4
Speed: 60 ft.
Space: 15 ft./10 ft.
Base Attack +14; Grapple +30
Attack: Gore +20 melee
Full Attack: Gore +20 melee and 4 lesser gores +15 melee and 2 hooves +15 melee
Damage: Gore 2d8+8, lesser gore 2d6+8, hooves 1d6+8
Special Attacks/Actions: Plane shift, powerful charge
Abilities: Str 27, Dex 14, Con 26, Int 2, Wis 11, Cha 9
Special Qualities: SR 20
Feats: Alertness; Weapon Focus (gore)
Skills: Listen +9 and Spot +12
Advancement: 15-28 HD (Huge); 29-42 HD (Gargantuan)
Climate/Terrain: Wilderness of the Beastlands
Organization: Solitary or herd (2-8)
Treasure/Possessions: None

Source: Planar Handbook

Plane Shift (Su): Although it has superb and imposing antlers, a gaspar has an even more remarkable defense mechanism: It can make its foes go away. If engaged in melee combat and seriously wounded or threatened (usually if reduced to half of its hit points), a gaspar activates its plane shift defense. Everyone within a 10-foot radius of the gaspar must make a DC 16 Will save or be transported to a random plane. All creatures caught in the same burst go to the same plane. The gaspar and any rider it bears are not transported. Once a gaspar uses its plane shift ability, it can't do so again until 1d4 rounds later. A gaspar can plane shift a maximum of four times per day.

Powerful Charge (Ex): A gaspar deals 4d8+16 points of damage when it makes a charge.

Gaspars are social herd animals that tend to avoid other species, and most creatures leave them alone. If harassed or attacked, a gaspar charges.

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.