The two blocks at each edge of every room are duplicated in the adjoining one, with the obvious exception of those at the top (not accessible) and the bottom (which is the river).

The villans names of Dr Blitzen and Donna are taken from two of the' reindeer in Clement Clarke Moore's famous Christmas poem "A Visit from St. Nicholas", written in 1823. However, Blitzen is also German for "flash" or gramatically incorrect German for "lightning (bolts)", which appropriately describes the planned super ray gun in the game. The name is possibly also a reference to Dr Blofeld, a recurring villain in the James Bond series.

The main theme tune is an excerpt from the third movement "Alla turca - Allegretto" of Mozart's Piano Sonata No. 11, composed c. 1783 and published the following year. The original piece, however, is played in A minor / C major, whereas the game's version is in D minor / F major, and played at a slower tempo.

The music that plays when Dan drowns in the river is a few bars of "The Sailor's Hornpipe", as heard annually in the Last Night at the Proms, at the end of Mike Oldfield's "Tubular Bells", or on the contemporary computer game, Booty.

The message on completing the game says "UNRAVEL THIS CODED MESSAGE: - NRIILIHLUG IFOVH LP THEN PHONE ... TO CLAIM YOUR PRIZE". The code simply swaps A <-> Z, B <-> Y etc, which decodes to "MIRROSOFT RULES OK".

The phone number given was Mirrorsoft's office number starting 01-377, which in 1985 was in Bishopsgate, City of London. In May 1990, this would have become 071-377, and since PhONEDay on 16 April 1995, 01377 has become the area code for Driffield, East Riding of Yorkshire. So if you try and ring the number now, nothing will happen as you will not have entered a number long enough; although that's probably better than annoying some random Yorkshireman.