I am running a Burning Wheel version of the Enemy Within. They are in the castle of the Wittgensteins and may soon run into Lady Ingrid and her swarm of mutant cats.
From the module “Mutant Cats
The cats vary greatly, but each has at least one visible mutation.
Some have long ears or long tails, some are strangely coloured
(bright blue, red and yellow stripes), others have human-like
hands, or long fangs, or multiple limbs or eyes. You should feel
free to describe any kind of mutation that comes to mind. These
cats have been thoroughly spoilt by Lady Ingrid. The other
residents of the castle try to avoid them, as they can be quite
vicious. The creatures are dreaded by the servants of the castle,
whom they have been known to attack, and more than one of
the beasts has developed a taste for blood that goes beyond mice
and small birds.”
MUTANT CATS
M 5
WS 40
BS -
S 20
T 10
I 60
Agi 40
Dex -
Int 10
WP 20
Fel -
W 30
I don’t know WHFRP at all, but there’s the Bonepicker in the Monster Burner (pg 303). The way they are handled is:
Swarm attacks can’t be Blocked
every 30-50 new members of the swarm gave +2 Pow and +1 VA to their attacks
These swarm rules are for things that seem about the size of bugs, so I might change that from 30-50 to maybe 3-10 or something. Depending on how deadly you want swarms to be, and how many cats you expect.
There’s no real verbiage on how to manage how many you harm, nor how to handle how many go down, it’s probably pretty specific. If I was running I’d probably make some calls around how many successes were gained over the obstacle.
I’ve no idea the scale of WFRP stats, so no idea how they’d transfer. But the MoBu has a cat (I don’t know BWHQ’s stance on the status of the former Creature Codex from the wiki so don’t want to just outrightly post).
I suggest that the dice penalties from wounds are a good measure for proportion of swarm lost: If the swarm’s lowest stat is a three, then a Light Wound knocks out about a third of them (incapacitation meaning they’re all killed or scattered). The wound penalties also nicely model their reduced numbers leading to reduced effectiveness.
I might give them immunity to Superficial Wound penalties – such incidental hits injure or kill one, but it’s not meaningful. Until you get three of them, then you’ve made a dent and the swarm may scatter (Light Wound Steel test).
You could probably stat it up as basically “a dude” using the Rogue Burner in the back of the main book, with the values dialed to your desired level of threat.
Turns out that the damage the cats did when they swarmed really was not enough. The player passed the fort test against toxoplasmosis. Though the crazy cat lady baroness was no match for exploding dice on a fire breath. It made sense for the swarm to scatter in the face of such pyrotechnics.
I used the stat block to represent all of them. I gave them a skill of swarm attack B5 but it did an IMS B3 B5 B7 with an add of 1. It ignores supis, has VA of 1 and default targets the leg instead of the chest. So the gang of cats attacks as 1. It’s lowest stat was B3 so 3 light wounds (or whatever combination) and the cats scatter. I think I gave it a MW of B10.