Pre postscript- sometimes you can get things so wrong, and try to read more into a piece than is going on. Everything below is my own speculation and assumptions going into overdrive. The word is XODUS and not FOIS. It was painted opposite Kleiner Shames and Subtle hence the recognition. I’m not sure who XODUS is, but I feel a bit stoopid. Never mind, I don’t expect anyone will read this nonsense anyway…
Aah, the genius of two brilliant artists conjuring up this amazing and highly unusual piece. It would seem that a Kleiner Shames visited Bristol over the Christmas period and hooked up with his old mate Subtle. The pair both produced pieces in the St Werburghs tunnel, and obviously had a bit of time left over to turn out this stunner.

Signed FoiSubtle, the collaboration presents with two distinct styles. My guess is that the letters FOIS are by Kleiner Shames, he always writes these letters but never quite like this, and the characters, a wolf holding a rabbit by the ears are by Subtle, in a bit of a departure from his writing. There is a message on the piece written backwards that says ‘one tin wonders’. I would think this refers to the two colours (plus black) that were used for the piece.
I cannot tell you how much I love this. It is quirky and retro, the characters look like early Disney creations. As I always say when Kleiner Shames comes to town, come back soon.