Uncover as much of the field as you can without touching a mine.

1. Tap a covered square to uncover it. A number counts the mines touching that square, and a blank clears everything around it.
2. Long press (or right click, or the Flag button) to mark a mine. A press you hold never digs, so a mark that does not take costs you nothing. Flags cost nothing and score nothing.
3. Tap a number whose mines are all flagged to open the rest of its neighbours at once. Quick, and it trusts your flags without checking them.
4. There is no bottom. Keep going until you are wrong, then play again as many times as you like.

Scored on CELLS UNCOVERED, and you can play the day as many times as you like, because Sweep keeps your BEST run rather than your first: your score IS the number of squares you uncover, with no ceiling on it, and 120 is par for the day. Ties break on FEWEST DIGS, since the same cells off fewer clicks means you read the cascades rather than clicking through them. Sweep pays at most 1 IQ point a day however long the run goes and however many runs you play, so nobody can grind their way up the standings: the real competition is today’s leaderboard. Sundays put more mines in the same field.