Four games, one claim: almost every named pattern in a game is an instance of one much smaller rule. Learn the rule, and the named patterns become things you recognise instead of things you memorise.
Each game gives you Learn (the pattern cards), Drill (positions to solve against a clock, scored), Play (the real thing), and Rules (the variant switches that make the same game behave differently).
Nothing leaves your browser. Your drill record is in localStorage and disappears when you clear site data.
Minesweeper is the one with the deepest treatment, because it is the one where "the sites disagree" is a real and specific problem rather than a feeling. See its Rules tab.
