Multi-coloured with stripes. Her patches of colour are large enough to have their own stripes, so it made sense, at least to me. Initially it was the Dark Cat of Chaos, the Striped Cat of Chaos, and the Plaid Cat of Chaos (Koshka, Iniki, and Patches, a.k.a. Secret Agent Fang). I tried calling Secret Agent Fang the Paisley Cat of Chaos, but it would never stick.

We frequently refer to the other two as 'the black cat' and 'the striped cat' (occasionally with a genitive pronoun, i.e., *your* black cat) and I have enough trouble not calling Autumn by the wrong name in the first place, it's easier to refer to her as the plaid cat.