Sonic Eraser

Overview

Sonic Eraser is a falling-block tile-matching puzzle game developed and released by Sega for the Sega Mega Drive exclusively in Japan through the digital Sega Game Toshokan service in 1991.

Similar to Sega's earlier puzzle game Columns, Sonic Eraser tasks players with manipulating four-block pieces as they fall into a 13×7 playfield in order to make matches of two-or-more of the same color/shape. The gimmick with this game is that the pieces are four-block tetrominoes similar to the Tetris series, but they cannot be rotated, with players instead rotating the block selection, similar to Columns.

Although the game is sometimes considered a spin-off of the Sonic the Hedgehog series, there is little relation to that series besides the inclusion of mascot protagonist Sonic the Hedgehog in the game's Versus mode. It received a very limited release at the time, as it was one of the few games for the Sega Game Toshokan service to neither receive a separate retail release nor an inclusion in any of the Game no Kanzume compilations. It remained in obscurity until an emulated version was released digitally for the PC in the early 2000's as part of Sega's Japanese-exclusive B-Club! service. It has not received any official release since.

Gameplay

Sonic Eraser plays similar to other falling-block tile-matching puzzle games, with players manipulating a random selection of four-block pieces (with five different types of blocks, each based on a color and shape) as they fall into the playfield to match blocks of the same type together and clear them before the playfield fills up.

Similar to Columns, players do not rotate the pieces themselves, and instead rotate their block placement (shifting the blocks counter-clockwise using the C button).

Scoring

In the game's standard mode, players are scored based on the amount of blocks cleared in a single match. There is no bonus scoring for chain reactions, instead counting as an additional match, and the is no bonus scoring for the game's level.

• 2 blocks - 200 pts.
• 3 blocks - 600 pts.
• 4 blocks - 1200 pts.
• 5+ - ?

Game Modes

The game's standard mode, known as "1P AND 2P", is played in single-player, with the option of having a second player playing independently with their own board and rules.

• Round Mode is a stage-based mode where players have three minutes to clear all copies of a sixth animated block type from the pre-populated board. If they manage to get stuck (having two of those blocks be more than one column apart, or leaving one block remaining), they can use A+C to Game Over.

• Normal Mode is an endless/marathon mode without any gimmicks. After a certain amount of points, the game's difficulty levels up and the pieces drop faster.

• Doubt Mode is similar to Normal Mode, but none of the pieces have a white square block. Instead, whenever a piece lands, one of the red triangle blocks have a random chance to change to a white square.

• Block Mode mode is similar to Normal Mode, but individual blocks are not affected by gravity until a match is made.

The game also has a dedicated Versus mode (known as 1P V.S 2P for two-player versus or 1P V.S COMP for one-player against a CPU opponent). In this mode, both players have the same set of pieces as they try to survive longer than the other. By making large clears at once, they can "attack" their opponent in two ways:

• By clearing 5-6 blocks at once, including chain reactions, the block selection for the opponent's next piece is hidden until it lands. As both players share the same queue, it is possible to read this piece by reading the queue.

• By clearing 7+ blocks at once, including chain reactions, a cinematic occurs with the player's Sonic attacking the other, stunning them and preventing the player from freely manipulating their pieces for a short time. Larger clears give longer stuns.