What an original take on the minesweeper formula! Now I want this on my PC and I totally see bank tellers around the world playing this while the line gets bigger.
Minor nitpick that didn't influence at all my rating was that I wanted to see what was installed on the PC when I clicked the "start menu" 😉.
One piece of feedback is that it could have more mechanics from minesweeper, like showing numbers (either to indicate the number of discoveries or the number of tiles without a discovery) and placing flags. It doesn't really matter in level 1 but on later levels it gets very tricky.