Amazing, thanks for the answer! Yeah forgot these boss mechanics. I had a great time playing it.
Now that I have played a bit there is a small QoL update that I would love to see for the release.
When users complete a number in a row or a column it should being grayed out or strikethrough. This would help players to more quickly and more easily realize what they have achieved and what's to find next, without having to rely purely on right clicked cells.
This would be a great addition in my opinion because it can feel a bit bloated.