I feel like I'm grokking the rules after a couple of runthroughs and a peek at the help page (the button on the bottom right). I'm liking the idea of this game but need to make better use of the monster counts that you see in the help page - mostly because a 100+ score will usually mean exactly on 100 level mine, so can be treated as "there is an adjacent mine" rather than "there are 100 points of monsters adjacent.

Two things bother me though.

The thing that I continue to find most confusing is that sometimes a square has a question mark instead of a number. From looking at boards after I lose there does not appear any pattern to this.

The other thing that's strange is the "wall" squares -- seems like a wall can take a couple of hits to break, you can't die from a wall, and you seem to get damage each time you hit it and an arbitrary amount of gold from breaking it. Does anyone have any better ideas on how these work?