Phargion (CR 5)

Medium Magical Beast
Alignment: Usually neutral
Initiative: +3 (Dex); Senses: darkvision 60 ft. and low-light vision

AC: 18 (+3 Dex, +4 natural, +1 shield [armblades]), touch 13, flat-footed 15; 22, touch 17, flat-footed 19 when rolled up
Hit Dice: 10d10+20 (75 hp)
Fort +9, Ref +10, Will +5
Speed: 10 ft., 40 ft. when rolled up
Space: 5 ft./5 ft.
Base Attack +10; Grapple +11
Attack: Armblade +12 melee
Full Attack: 2 armblades +12 melee
Damage: Armblade 1d6+1
Special Attacks/Actions: -
Abilities: Str 13, Dex 17, Con 14, Int 5, Wis 14, Cha 8
Special Qualities: Armblade shields, rapid movement
Feats: Dodge; Endurance; Mobility; Weapon Focus (armblade)
Skills: Balance +10, Jump -9, and Tumble +11
Advancement: 11-15 HD (Medium); 16-30 HD (Large)
Climate/Terrain: Temperate plains
Organization: Solitary or flock (2-12)
Treasure/Possessions: None

Source: Miniatures Handbook

Armblade Shields (Ex): A phargion's two armblades provides +1 shield bonus to its Armor Class, as though it were using weapons and had the Two-Weapon Defense feat.

Rapid Movement (Ex): A phargion can roll itself into a wheel as a free action or unroll as a move action. As a wheel, its speed increases to 40 feet (Jump bonus improves to +7). A phargion can not attack while in this form but gains a +4 bonus to Armor Class.

A phargion rolls its way into combat but unrolls (as a move action) before attacking. It slices its prey with its armblades and feasts on the spot before rolling on to find new prey.