I finally did a good run, ended on Layer 23 with 66489 points.
It was fun! I like the music when playing and love the intro one. The game could 100% come from a lost cartridge and the gameplay loop is super addictive, the game gets super tense as your time is melting.
For a time I thought I was killing the enemies with the drill, it's probably just me yet maybe the miner might flicker (or cry ;) ) when he gets hits.
Thanks for sharing!