Very impressive that you put the extra work into a SGB format. And a link format! I did load two copies onto linked cartridges to try it out but didn't have time to discover: How does the one relate to the other in Mystery Quest?
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Hi Sloopy! Thanks for checking out the game, once mystery quest is booted both players are assigned the same seed, this allows for the puzzles being synced to their instance, bringing variation to each play session! They both have hints in their game which should help the other player advance in their playthrough, so communication is key! Hope this answers your question!