{"id":23585,"date":"2022-12-13T09:00:21","date_gmt":"2022-12-13T17:00:21","guid":{"rendered":"https:\/\/www.gmpuzzles.com\/blog\/?p=23585"},"modified":"2025-09-03T10:57:20","modified_gmt":"2025-09-03T17:57:20","slug":"rail-pool-by-martin-ender","status":"publish","type":"post","link":"https:\/\/www.gmpuzzles.com\/blog\/2022\/12\/rail-pool-by-martin-ender\/","title":{"rendered":"Rail Pool by Martin Ender"},"content":{"rendered":"

This puzzle style was created by Martin Ender (first example here<\/a>), and was one of the “new generation” of puzzles at the 2022 World Puzzle Championship. While it won’t be in our upcoming Loop Variety Collection 2, we are planning to have some more Rail Pool in GMPuzzles projects in the future.<\/i><\/p>\n

\"Rail<\/p>\n

PDF<\/a><\/p>\n

or solve online<\/a> (using our beta test of Penpa-Edit tools in default linex mode where left-click+drag draws line and right click marks X’s)<\/p>\n

Theme:<\/b> Tetris<\/p>\n

Author\/Opus:<\/b> This is the 1st puzzle from guest contributor Martin Ender.<\/p>\n

Rules:<\/b> Draw a single, non-intersecting loop that passes through the centers of all cells, including clue cells. Clues represent all of the different lengths of the straight line segments that pass through all cells within the region, either partially or fully contained by that region. Each number within a region must be represented by at least one line segment. Each “?” represents a positive integer; if a clue cell has more than one “?”, all numbers and \u201c?\u201ds in that clue must be different from each other.<\/p>\n

Also see this example:<\/p>\n

\"Rail<\/p>\n

Difficulty:<\/b> 2.5 stars<\/p>\n

Time Standards (highlight to view):<\/b> Grandmaster = 1:30, Master = 2:45, Expert = 5:30<\/span><\/p>\n

Solution:<\/b> PDF<\/a> and solving video<\/a>.<\/p>\n

Note:<\/b> Follow this link for other Loop\/Path puzzles<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"

This puzzle style was created by Martin Ender (first example here), and was one of the “new generation” of puzzles at the 2022 World Puzzle Championship. While it won’t be in our upcoming Loop Variety Collection 2, we are planning to have some more Rail Pool in GMPuzzles projects in the future. PDF or solve […]<\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[124,3,55],"tags":[15,56,205],"class_list":["post-23585","post","type-post","status-publish","format-standard","hentry","category-loop2","category-puzzle","category-variation","tag-wednesdaythursday","tag-variation-2","tag-railpool"],"yoast_head":"\nRail Pool by Martin Ender - The Art of Puzzles<\/title>\n<meta name=\"description\" content=\"While the tetris blocks may be falling into place, can you place the whole Rail Loop following the rules (style and puzzle by Martin Ender).\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.gmpuzzles.com\/blog\/2022\/12\/rail-pool-by-martin-ender\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Rail Pool by Martin Ender - 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