Medium Magical Beast?
Stats of component creatures:
Wolverine (M): Str 14, Dex 15, Con 19, Int 2, Wis 12, Cha 10, +2 natural armor
Speed: 30 ft. (6 squares), burrow 10 ft., climb 10 ft
Fox (S): Str 11, Dex 19, Con 11, Int 2, Wis 12, Cha 7, +0 natural
Speed: 40 ft.
Taking the best of both yields:
Str 14, Dex 19, Con 19, Int 2, Wis 12, Cha 10, +2 natural armor
Speed: 40 ft. (8 squares), burrow 10 ft., climb 10 ft
Both have scent.
Rage (Ex): A wolverine that takes damage in combat flies into a berserk rage on its next turn, clawing and biting madly until either it or its opponent is dead. It gains +4 to Strength, +4 to Constitution, and –2 to Armor Class. The creature cannot end its rage voluntarily.
Skills: Wolverines have a +8 racial bonus on Climb checks and can always choose to take 10 on Climb checks, even if rushed or threatened.