The Tyrannofex is a living biofortress. Armed with weapons normally found on battle tanks. It looms over the battlefield on it's scythed limbs, spitting acidic death at infantry and armour alike. 

The Tervigon acts as a broodmother to Termagant swarms, bolstering those around it while reinforcing their numbers as they spawn from it's incubation sac. A potent Psyker it also acts an a Synaptic anchor keeping units around it under complete control of the Hive Mind.