This was to be the sequel to Valkyrie 17 and announced to be released in September 1985 (Home Computing Weekly, 17-23 September 1985, No. 130, page 9). It was partially finished on the C64 but, for reasons unknown, never released.
Games That Weren't has a page about the game.
(According to page 69 of the October 1986 adventure column in Your Sinclair, Ramjam had decided that Three Days in Carpathia was no longer the sequel to Valkyrie 17, and would be a completely different adventure, with a true sequel Valkyrie 18/Valkyrie II released later.)
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