Deep down in many of us, there a still an ancestral yearning to be in the mines, and is true of me it seems.
This is the definition of simple premise, well executed. It's super easy to pick up and understand right away, the goals are clear and it's a nice fun loop with neat presentation. It's a great 'switch my brain off' kind of game where I don't have to think too hard. I made it to the 80k checkpoint .
I would have loved if I could have continously moved by holding the 'W' key because once the tunnels get quite long it can become a little much to smash the key repeatedly; however I do understand this may have been a design decision to incentivise lots of smaller tunnels rather than a few long ones? If that's the case I would prefer the option to have it in keydown rather than keyup (even if that's an ingame setting). But that's literally the only thing.
I don't know how this will rate amongst the 'die-hard' dungeon crawler fans. However from my perspective, it follows all the rules and I had fun, which is all that matters. Great job, and thank you.