A native inhabitant of Labion (a planet in the Space Quest universe), the Terror Beast is a very primitive and violent creature. It moves around by rapidly whirling (much like Taz), and almost nothing can withstand it.
Fortunately, the Terror Beast is rather stupid. They can be easily quelled with a puzzle (such as the "cubix rube"*), and can be attracted with a Labion Terror Beast Mating Whistle, available from the Gippazoid Novelty Company.
*Yes, that is correct; it's a spoof of the infamous Rubik's Cube. You can find it (in the game) in the locker, right near the start.