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Mario Clash is a game released for the Virtual Boy in 1995. It is also the first 3D stereoscopic Mario game. The game is a return to the style of the original Mario Bros. To progress through the game, Mario must knock enemies off platforms using Koopa Shells. There are always two Koopas; if one gets knocked off, another one takes its place. Many enemies need to be hit from the side, thus Mario must throw Koopa shells from the background to the foreground and vice-versa in order to knock them off.
Story from the instruction booklet
The Clash House Tower has been invaded by bad guys! It's up to Mario to clear them out, throwing Koopa shells to knock them away. Take care as you battle in dangerous rooms of narrow ledges connected by pipes.
The game received mixed reviews. ScrewAttack named this video game "The second worst Mario video game of all time", while other reviews were kinder. The Video Game Critic gave it an A and called it a "must have for Virtual Boy owners".