Namco‘s Mr. Driller first appeared in arcades in 1999, and this PlayStation version (pretty much the arcade version, plus a bunch of extras) came out in 2000.
Mr. Driller has been described as a cross between the classic Namco arcade game Dig Dug, and Tetris. In fact, Mr. Driller was initially being developed as a Dig Dug title before it was later changed (even more meta, the main character of Mr. Driller is Susumu Hori, the son of Taizou Hori, who was the star of the original Dig Dug game).
You dig – using a drill (of course) – downwards, into a huge pile of shaped blocks. And – depending on their shape – the blocks will either stay stable, or collapse, as you dig deeper. Any falling blocks will squash you, so you obviously have to avoid them. You also have limited air, and have to top up as you go, by picking up green capsules that occasionally appear. Drilling any of the brown, ‘solid’ blocks you encounter will cost you 20% of your air total per block drilled, so drilling them is a last resort.
Mr. Driller features an Arcade mode, with the complete arcade game, plus a Time Attack mode, and also a Survival mode. The graphics and presentation are absolutely top notch throughout, and the game is a joy to play. What more could you ask for?
More: Mr. Driller on Wikipedia