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.…
It took me a second to figure this out, too. Here's a couple hints (base64 encoded to prevent spoilers for other folks:
Hint: QXQgdGhlIGRlYXRoIHNjcmVlbiwgdGFrZSBhIGNhcmVmdWwgbG9vayBhdCB3aGF0J3MgKipuZWFyYnkqKiB0aGUgcXVlc3Rpb24tbWFyayBzcXVhcmVzCg==
Answer: VGhlIGdhemVyIGVuZW15IG1ha2VzIGFkamFjZW50IHNxdWFyZXMgc2hvdyBhID8uIFRoaXMgZWZmZWN0IGV4dGVuZHMgcGFzdCB3YWxscyBhcyB3ZWxsLgo=