Hit Dice: 6d8+30 (51)
Speed: 45 ft. (9 squares), swim 45 ft.
Armor Class: 16 (+1 Dex, +6 natural, -1 size), touch 11, flat-footed 16
Base Attack/Grapple: +1/+9
Attack: Bite +9 (3d6+8)
Full Attack: Bite +9 (3d6+8)
Space/Reach: 10 ft./5 ft.
Special Attacks: -
Special Qualities: Low-light vision
Saves: Fort +10, Ref +4, Will +2
Abilities: Str 27, Dex 13, Con 21, Int 1, Wis 12, Cha 2
Skills: Climb +12, Hide +2*, Listen +4, Move Silently +1, Spot +4, Swim +16
Feats: Alertness, Great Fortitude, Improved Natural Attack
Environment: Warm forests
Challenge Rating: 4
Dire Monitor Lizards are anywhere between 8-16 long, weigh well in excess of 500 pounds, and are viciously agressive.
Skills: A monitor lizard has a +8 racial bonus on any Swim check to perform some special action or avoid a hazard. It can always choose to take 10 on a Swim check, even if distracted or endangered. It can use the run action while swimming, provided it swims in a straight line.
In forested or overgrown areas, Dire Monitor Lizards gain a Hide bonus of +4.
Dire Template Courtesey of the Immortal's Handbook