As a miner, your goal in life is to collect enough diamonds to unlock the exit to the next level, all the while happily digging through levels with some impassable walls and... boulders of course! Lots of them.
Boulders obey the laws of gravity, and as such will happily fall onto your head lest you be vigilant not to trigger their fall, or fast enough to dodge them.
Later on, monsters also roam the underground corridors and give you a chance to further refine your skills at last-second boulder dodging - you let the monsters get the hit on the head!

This particular installment of the game boasts 24x4 levels of digging fun.

All 24 levels in 6 worlds have been changed. I've tested each level to make sure that it can be completed without softlock yourself in any level. The levels start out pretty simple but start getting extremely challenging towards the end.

Database match: Boulder Dash (Europe)
Database: No-Intro: Nintendo Entertainment System (v. 20180803-121122)
File SHA-1: DDEE3729DD7CA75A9225418440FA77D4B50DF8D3
File CRC32: A00653E1
ROM SHA-1: EA170B7F53BC1DF483976641DE4B2D02716ED233
ROM CRC32: E5FCC4C1