Wario's Throne is a stage in Mushroom Kingdom Showdown. It was added in v.0.6. The stage is based off of the final room in Wario's Castle in Super Mario Land 2 : The Six Golden Coins.
Wario's Throne is currently the only stage based off of a Game Boy game. (Being Super Mario Land 2: 6 Golden Coins).
This is one of the fewer stages (Along with Mushroom Plains) where you can't fall off screen.
This stage was redesigned in v.0.9. A Game Boy-like border was added around the area. This design is reminiscent of the Dreamland stage from Super Smash Brothers for Nintendo 3DS.