Tametsi 1.79

Tametsi is a difficult logic game played on a set of tiles, in which you must use the clues provided to discover and mark hidden mines.Notable features
a variety of tilings beyond the standard square grid
100 increasingly difficult hand-designed levels
60 extra puzzles to unlock
mid-level progress is saved automatically
over 40 hours of gameplay

If you get stuck, there are also drawing tools for taking notes.
Note: there is no in-game music.
Although Tametsi can be very challenging, every level can be completed using logic alone: guessing is never required.