Other games that do this: https://en.wikipedia.org/wiki/Planarity https://en.wikipedia.org/wiki/Planarity https://web.mit.edu/xiphmont/Public/gPlanarity.html

Other games that do this: https://en.wikipedia.org/wiki/Planarity https://en.wikipedia.org/wiki/Planarity https://web.mit.edu/xiphmont/Public/gPlanarity.html https://web.mit.edu/xiphmont/Public/gPlanarity.html Untangle (in sgt-puzzles)