Need I mention than a knarloc is from the other side of the galaxy roughly 100,000 LY away. Even assuming Warp travel can be 100xLS it wouldn't even have evolved when the last ship that arrived in the spinward front from Tau space left.
Why not just invent something, give it a suitably fearsome name and description and GM it. Meaning that it dies when the players have worked hard enough, rather than a specific number of wounds, TB and such that can be defeated by a cheesey choice of weaponry and abilities?
A terrifying juggernaut of toxic spines, vicious teeth and scything claws the Spine-Hulk is a native to the swamps of the deathworld Exampil.
Thought to be distantly related to the porcupines of ancient Terra. The spine beast stands on six thickly muscled legs, and commonly towers over six meters, although large males can reach over ten meters in height.
The Spine-Hulk is famously aggressive, attacking anything it perceives as a threat primarily by firing three meter long toxin-laced spines, although enraged males and brooding females have been known to close and attack with their ferocious teeth and claws.
Despite it's intense aggression and ferocious territorialism the Spine-Hulk is a herbivore, and the was primary food souce of the now-extinct Exampillian Gore-Thirster.
BS 50 (Spines) Rng 15, 1d10+2 pen 2 Toxic(3)
WS 70 (Teeth/claws) 2d10+6 pen 4
Each turn the SH takes damage take WP test, if failed the SH fires D5 spines at random (roll scatter), if passed the SH targets D3 spines at the source of the attack (if aware of the source.)
Edited by Askil, 04 August 2014 - 02:37 AM.