|Androvandi - Public Domain|
The Cave Otter appears to be a cross between an otter and a wild boar. While primarily found deep in wet underground caves they can also be found around fast flowing waterfalls and rapids above ground. While preferring water to land, they will often venture upon land to hunt. The stand nearly 2 feet tall and 3 feet from snout to tail.
Cave Otters attack with their fearsome bite. Their tusks can be deadly. On an attack roll of a natural 19 or 20, a limb of the opponent is impaled, causing double damage.
Primarily solitary creatures, they can sometimes (1 in 6 chance) be found in a mated pair. Much like otters, they are attacked to shiny things, and their nests have been known to hold coins and gems they have found prior.
Swords & Wizardry Complete
Hit Dice: 4
Armor Class: 5 
Attacks: 1 Bite (1d10) / Special - On a roll of 19 or 20, inflicts double damage with tusk impale
Saving Throw: 13
Move: 9/18 (swimming)
Challenge Level/XP: 5/240
Swords & Wizardry Light
AC: 5 HD: 4 Attacks: bite (1d6+2) Move: 9 (18 in water)
Special: On a roll of 19 or 20, inflicts double damage with tusk impale