Disgraced Bioteknists Skar Venn knew exactly how to win back the favour of the House of Artifice: Reverse his clans wasting phage, without giving up their technology or risking their advanced intellects, and the solution had been right under their noses:

Venn attempted to recreate his House's historic work on GeneSmithing in the historical creation of the Goliaths and the House of Chains.

There was always method to the madness however... Naturally he began by experimenting on rats. 

Trialing a variety of cyberteknic, rad and pharma-chemystry 'treatment' on his test subjects, Venn only succeeded in enhancing their aggressive scavenger instincts as well as their already Underhive variety proportions. In desperation he exposed a small number to an unusual high-energy crystalline mineral found in an uncovered Archeotek vault. 

Exact details of Project SK:VN and Venn's research are lost, however, as the Bioteknist was found dead- his workshop ransacked, and much of his Tek and wargear stolen in what was blamed on a Goliath raid (such was the mindless destruction).

Since then, CogPort has seen a rise in salty tales, or tails, or giant-er giant rats, glowing green eyes, whirling mechanical limbs, and chittering in the dark corners.