Smilodon (CR 5)

Large Animal
Alignment: Always neutral
Initiative: +2 (Dex); Senses: low-light vision, scent, Listen +8, and Spot +8

AC: 15 (-1 size, +2 Dex, +4 natural), touch 11, flat-footed 13
Hit Dice: 9d8+27 (67 hp)
Fort +9, Ref +8, Will +8
Speed: 40 ft.
Space: 10 ft./5 ft.
Base Attack +6; Grapple +17
Attack: Bite +12 melee
Full Attack: Bite +12 melee and 2 claws +10 melee
Damage: Bite 2d6+7/x3, claws 1d6+3
Special Attacks/Actions: Augmented critical, improved grab, pounce, rake 1d6+3
Abilities: Str 24, Dex 14, Con 16, Int 2, Wis 14, Cha 6
Special Qualities:
Feats: Alertness; Dodge; Mobility; Spring Attack
Skills: Balance +6, Hide +2*, Jump +15, Listen +8, Move Silently +6, and Spot +8
Advancement: 10-18 HD (Large)
Climate/Terrain: Cold forests
Organization: Solitary, mated pair, or pride (3-12)
Treasure/Possessions: None

Source: Frostburn

Augmented Critical (Ex): A saber-toothed tiger deals triple damage if it scores a critical hit with its bite attack.

Improved Grab (Ex): To use this ability, the saber-toothed tiger must hit with a bite or a claw attack. It can then attempt to start a grapple as a free action without provoking attacks of opportunity. If it wins the grapple check, it establishes a hold and can rake.

Pounce (Ex): If a saber-toothed tiger charges a foe, it can make a full attack, including two rake attacks.

Rake (Ex): A saber-toothed tiger gains two additional claw attacks against grappled foes or foes it pounces on (attack bonus +10, damage 1d6+3). Rake attacks are not subject to the normal -4 penalty for attacking with a natural weapon in a grapple.

Scent (Ex): A saber-toothed tiger can detect opponents within 30 feet. The exact location is not revealed unless the creature is within 5 feet.

Skills: Saber-toothed tigers gain a +4 racial bonus on Balance, Hide, and Move Silently checks.

*In forest terrain, their Hide bonus improves to +8.

The saber-toothed tiger is a canny hunter, rarely greedy but with a large enough appetite to require frequent kills. Saber-toothed tigers do not chase down prey over long distances. Instead, they leap or charge from ambush, waiting for prey to come close before attacking.

Groups of saber-toothed tigers work together much like lions and other social hunting cats; one group will startle prey, sending it running directly into a second group of tigers. They sometimes ignore motionless prey.