After having played for a bit longer, I have found a few things that I would like to see in addition to hotkey for pen/pencil toggling. 1) Shortcut to black out all unfilled spaces in a column/row (maybe this would trigger if all the numbers above/to the left of that column/row were clicked). 2) If a tile's been blacked out, accidentally clicking it should not immediately switch it to blue (this costs me hearts sometimes); maybe instead clicking a blacked space should clear the space of all marks.
Yep, that is one of those little "whoops" that happened when I tuned the game to be shorter. A few costs go whacked out and it's on me. The overall game length is what I wanted but there are those strange costs. DANG IT! That said, thanks for the comment and the play! Best, -Tim
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1) and 2) done .. enjoy! :)