Sonic Eraser (Japan) (SegaNet) [En by D v1.0]

Sonic Eraser is a puzzle game originally released exclusively in Japan for the Sega Mega Drive via the Sega Meganet (SegaNet) modem service in 1991. This version is a fan-made English translation patch ("En by D v1.0") that replaces the original Japanese text with English, making the game playable for a wider audience. Unlike the mainline Sonic platformers, this is a falling-block puzzle game that borrows characters and music from the Sonic universe, giving it a unique place in the series' history as a Japan-only oddity.

The objective is straightforward: colored blocks drop from the top of the screen in pairs, and you must swap or rotate them to line up three or more of the same color horizontally or vertically. Clearing blocks causes new ones to fall, and the chain reactions can speed up the pace. The game features a generic versus AI mode where you compete to fill the opponent's meter, as well as a one-player endless mode. Controls are simple: move the blocks left or right, rotate, and drop them quickly.

For fans of classic puzzle games or Sonic completists, this is a neat curiosity that shows Sega experimenting with the brand in early online gaming. The English patch finally makes it accessible without needing to navigate Japanese menus. It's not a deep or complex puzzle game - it's a straightforward block-matching experience similar to Columns or Puyo Puyo, but with a Sonic coat of paint. If you enjoy retro logic puzzles or want to see a lesser-known slice of Sonic history, it's worth a few rounds.