Bred during the civil war that ended the First Republic by the Kahraman, the Canavar are huge armored 200-foot tall centipede-scorpion monsters. The proved unstoppable on the field until the Dusman developed the Raknar specificially to fight them. Ultimately, their opponents eradicated both the Canavar and the Kahraman from the galaxy.
One of the few laws scrupulously enforced in the Galactic Union is the prohibition against breeding Canavar. Despite this, and the belief that Canavar were completely destroyed, there are now rumors that they have been seen again after thousands of years.
From the Books: "At first, Jim didn’t think it was real. How could such a thing take animate form? Half centipede with two sets of serrated claws, the thing rolled out of the ship on hundreds of legs and reared up, up, and up until it was 100 feet in the air, its glistening red eyestalks level with his own head. At least that much or more remained on the ground bracing the part that rose to oppose him. Its entire length was covered in thick brown armor plates. Segmented mouthparts broke open in what could be called a head, and it screamed a nauseating challenge that tore at his mind like gauntleted fingers on a chalkboard. Claw-like pincers snapped as it turned and moved lateral to him, in front of the transport."
- Cartwright's Cavaliers, p.