The following text is from the TZX Vault

Underwurlde, the second game in the Sabreman series had three seperate exits from the castle. Each exit had a different congratulations screen naming another adventure in the Sabreman saga. Exit one named Knight Lore which was released at the same time as Underwurlde. Exit two named Pentagram which was released in June 1986. The third exit named Mire Mare which was never published. The game was previewed on page 108 of the June 1987 issue of Sinclair User and was also featured on page 69 of the November 1987 issue of Sinclair user.

The following text is from Ultimate Wurlde

The first thing you have to appreciate is that the Mire Mare story is entirely linked with the sale of part of the company to US Gold.

Although Mire Mare was coded before Gunfright the Stampers were already planning to bail out of the market by selling off part of the company to US Gold, and they wanted to keep Mire Mare back as a Grand Finale - given the popularity of Sabre Man this was classed as a good idea, so Gunfright was completed and released first.

At this point the part-takeover moved along quicker than expected and US Gold took control just after the release of Gunfright. It soon became apparent that they were not interested in developing software for release on the Ultimate label (which in my opinion was a good idea, most US Gold stuff was rushed, full of bugs and excuse my french f*****g s**t). They were more interested in taking all the back catalogue and squeezing the remaining life out of them by putting them on the £2.99 KIXX label.

As you can expect this really upset the UPTG / AC&G team, so much so that when US Gold approached Chris and Tim asking where this planned Mire Mare title was as they would like to put it out on the KIXX label they were told that it was not finished.
(Although it basically was!)

Rob: [Interrupting] I wonder if there is a legal situation with Mire Mare then, which might explain why the Stampers have never cleared up the mystery of whether or not it actually exists. I mean, maybe if they suddenly disclose that it does exist in a completed (or mostly completed) state, then whoever owns US Gold now might have a stake in it?

Well, US Gold were told that the game was still under development and that it still needed another 6 months work to complete - US Gold did not want to invest money in completing this game so it was shelved - but it does exist - I have seen it, I have played it.

As far as I was aware, all the artwork had been made and Ultimate were going to return to the big fat cardboard packaging for this game - although this had not been confirmed and I had not seen this (as I departed some weeks before). I can only now assume that the packaging did arrive.

Here are the box images for the Sabreman series:-

Underwurlde
Mire Mare
Pentagram
Knight Lore