One the most recognizable versions of Tetris can be found on the original NES, but it lacks some of the features we now consider standard for the puzzle game. One of the biggest omissions is “hard drop,” which lets you save precious time by instantly slamming a piece into position without waiting for it to fall, and programmer Stephen Sherratt took it upon himself to get the feature working in the classic NES version, complete with a "ghost" piece for guidance.

As he explained on his website Grid Bugs, Sherratt decided to add two related features to the NES Tetris game. The first is the hard drop itself, accomplished by pressing up on the directional pad like it’s done in most other Tetris games. The second modification he made added an outline of the currently controlled piece to wherever it was set to land, making the hard drop more accurate. Again, this is a feature seen in pretty much all modern Tetris games such as Tetris 99 and Tetris Effect. In the challenge video below, one player even hard dropped every single piece he got in Tetris 99.

Sherratt made use of a program using the Rust programming language and, combined with his own NES emulator, it made it easier for him to experiment with changes. He had to write instructions for the outlined “ghost piece,” for instance, so it appeared in the correct spot based on how many movements it would take before the real piece collided with something.