Underground Adventure is an NES homebrew game made for the 2019 NESmaker Byte-Off Competition. It has a simple setting of two guys finding a cave that leads to an underground maze full of gems and monsters. They must then collect as many gems as they can under a time limit, avoid (or kill with a special item) any monsters along the way, and go back the way they came.
Cephla, LoganTheTASer, and DrD2k9 save 10 frames over the previous run by optimizing the jump leading to the floor clip that skips a huge part of the game.
You can get the game here.
Watch this run being played back on a real console.