XL-up maze

Way back in 2005 I turned the grand old age of 40 and designed a maze to mark the passing of the years. Starting from the central square, step out the roman number sequence from I to XL (1 to 40), starting I, II, III, IV etc. The roman-numeral sequence doesn't stop at 40 however, so as a secondary challenge why not see how much further you can go... 50? 60? 70?

New January 2021: XL-Plan is a surprisingly tricky twist on original XL-up, implemented in puzzlescript (credit: Mark Richardson). There is also a puzzlescript implementation of original XL-up playable here (credit: Guilherme Tows) which works very nicely on touch sensitive devices.

XL-up maze
Click below to play


Step out the roman numeral sequence from I to XL (1 to 40) using grey squares to punctuate the sequence. So that's I,II,III,IV,V etc using a grey square to mark each comma. Hint: keep an eye on the rolling ticker-tape underneath the grid if you can't remember how to count in roman numerals.


Use Restart (Action), or hit space, to reset the puzzle.
Hit 'u' to unwind the move-sequence to last grey-square (can be repeated to unwind as far as desired).


Use the cursor keys to move. At each move you can step to any adjacent square (left, right, up, down). Note, the same letter can be used many times, even within the same numeric.


Back in 2005 I asked the question... is it possible to construct an alternative 7x7 grid where the sequence can run even deeper? In September 2006 Ben Small did just this and found a maze that runs even deeper than my original maze. Ben's grid was thus added to the applet in 2006, as a second challenge.

applet, concept & maze design - © Andrea Gilbert - 2005
Ben's challenge maze - © Ben Small - 2006
applet JS conversion - cheerpj transpiler from Leaning Technologies - 2020