The title was first published by Trevor Toms for the ZX81 in The ZX81 Pocket Book.
Also available in German.
The same system was subsequently used for at least some of the games from Phipps Associates.
The original game was ported to OPL and the Psion II by Jim Mahaffey, and the C64 by Wane Murray.
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Useless piece of trivia: The game engine used by Phipps Associates for Magic Mountain, Pharaoh's Tomb, etc. seems to be based on the one from this game.
I'd hardly call that useless :)
There's no "seems" about it. Trevor Toms worked for Phipps Associates, the book from which it comes was published by them in the UK, and crucially, if you break into the ZX81 versions of the programs, you can list them and print the variables and they agree exactly with the method explained in the book.
By the way, the program unPhipps - available on the IF Archive - will "decompile" (wrong term for this system, really) both Alzan and the Phipps games.