Diprotodon (CR 5)

Large Animal
Alignment: Always neutral
Initiative: +0; Senses: low-light vision, scent, Listen +9, and Spot +9

AC: 14 (-1 size, +5 natural), touch 9, flat-footed 14
Hit Dice: 9d8+36 (76 hp)
Fort +10, Ref +6, Will +6
Speed: 40 ft., burrow 10 ft.
Space: 10 ft./5 ft.
Base Attack +6; Grapple +18
Attack: Gore +13 melee
Full Attack: Gore +13 melee and 2 claws +8 melee
Damage: Gore 1d8+8, claws 1d8+4
Special Attacks/Actions: Trample 2d6+12
Abilities: Str 27, Dex 10, Con 18, Int 2, Wis 13, Cha 11
Special Qualities:
Feats: Alertness; Improved Natural Attack (claw); Iron Will; Run
Skills: Listen +9 and Spot +9
Advancement: 12-18 HD (Large); 19-27 HD (Huge)
Climate/Terrain: Warm deserts
Organization: Solitary or pair
Treasure/Possessions: None

Source: Sandstorm

Trample (Ex): Reflex half DC 22. The save DC is Strength-based.

Although mild-mannered in general, a diprotodon is intensely territorial and does not hesitate to stamp an intruder into the ground. A diprotodon can move as quickly as a camel, despite its lumbering appearance, and when it charges, it often catches opponents off guard.