What the three difficulties actually change
The difficulty names aren't labels we picked by feel. Every board is carved by the same generator and then solved by a solver that only uses human deductions, so we can measure them. Over a sample of 40 boards per level: easy boards start with about 9.1 given cells and take about 26.9 forced steps, and 0% of them need the hardest technique; medium boards (the same level as the daily) start with about 5.7 givens and take about 30.3 steps, with 0% needing it; hard boards start with about 5.7 givens, take about 30.3 steps, and 100% need it. "The hardest technique" means listing the few ways a half-finished row or column could still be completed and keeping only the cells common to all of them — the hint button will show you when a board calls for it.
Hard mode is where the generator refuses any board that the three basic rules alone can finish, so expect at least one of those enumeration steps in almost every one. Easy mode adds a few givens back after carving so the opening is never blank. Whichever you pick, the board has exactly one solution and never needs a guess.
Tango without the daily limit
Love Tango but hate waiting until tomorrow for the next board? This is unlimited play: every board is freshly generated, guaranteed to have exactly one solution, and solvable by pure deduction — never guessing. Pick Easy to learn the patterns, Medium for the classic daily feel, or Hard for boards that demand deeper line-by-line reasoning.
New to the rules? Start with the how-to-play guide — it covers every solving technique from opening moves to advanced eliminations. Or warm up with today's daily puzzle and keep your streak alive.