Avarus' powerblade was similarly ineffective, and he was taken off guard as the machine whirled suddenly with startling speed for something so ungainly. The barrel of the energy cannon caught the Tempestor Prime's head a glancing blow and he fell to the ground, stunned despite his helmet. The ork walker bellowed again and raised one clawed foot, ready to stamp on him.

Choke Point pg. 20-21