n medium beast troll 

Perception +6; darkvision, scent (imprecise) 30 feet

Skills Acrobatics +6, Athletics +11, Stealth +8, Survival +6

Str +4 Dex +1 Con +5 Int -4 Wis +1 Cha -2

AC  17; Fort +14, Ref +8, Will +6

HP 65, regeneration 15 (deactivated by acid or fire)

Speed 35 feet

Melee [>] jaws +11, Damage 1d12+4 piercing plus Knockdown and bloodfire fever

Bloodfire Fever (disease) Saving Throw DC 18 Fortitude; Stage 1 carrier with no ill effect (1 day); Stage 2 enfeebled 1 (1 day); Stage 3 enfeebled 1 and clumsy 1 (1 day); Stage 4 enfeebled 2 and clumsy 2 (1 day); Stage 5 enfeebled 2, clumsy 2, and fatigued (1 day)

Pack Attack The trollhound deals an extra 1d6 damage to any creature within reach of at least two of the trollhound's allies.

Bestiary 2, page 268.