Here's an improbable entry from the Annex-of-Ideas back catalogue: the toilet-obsessed humour weekly THE BOG PAPER, launched in November 1989 (making it a contemporary to the similarly short-lived THE INCREDIBLE HULK PRESENTS).
This is a massive departure from the usual Marvel UK style: heading in the direction of comics-for-big-kids like VIZ. I can only assume that Marvel's mandarins looked at the collapsing British comics market and thought humour titles looked a better bet than traditional action/ adventure fare (a genre that had gone into steep decline since the middle of the decade).
Marvel UK had tentatively toyed with humour comics before (notably the Mad-inspired FRANTIC and MARVEL MADHOUSE in the early eighties) but those were reprint-based monthlies. This was an all-new weekly, with all the origination costs that go with it.
May of the same year had seen the launch of IT'S WICKED! - a humour weekly in the MONSTER FUN tradition - which used that annoying ectoplasm Slimer from THE REAL GHOSTBUSTERS as its star. Despite the media tie-in (and, lets face it, M-UK bunged the Ghostbusters in every possible comic during this period) and some unsubtle attempts to clone the look of DC Thompson's fare, it shuttered after only 17 issues.
I've showcased the weekly's most memorable strip - DOCTOR PHOO (do you see what they did there?) but other strips included Flush Gordon, Chicken Vindaloo, King John, Super Lu and other shit-based strips.
So obscure is the BP that I'm not sure how many issues in clocked-up, I'm betting no-more (and quite possibly less) than 15.