Vortex

The Vortex in Wario Land 4 is a wormhole where Wario can travel between the real world in the Golden Pyramid, and the levels in picture frames. The opening and closing of the Vortexes are controlled by the many Frog Switches in the game. Before entering any of the eighteen levels, Wario jumps on the Frog Switch, which opens the Vortex. Entering it will send Wario to the beginning of that level, and the Vortex will close behind him. The only way to reopen the Vortex is to find the Frog Switch in the level, but at the same time, searching for the Keyzer (which would open the next level), and the four Jewel Pieces (which grants access to the boss door). When the Frog Switch is hit within the level, a bomb will appear underneath it, and a time limit will appear at the top of the screen. That is the amount of time that Wario has to find the Vortex and escape back to the Pyramid. If the time runs out, Wario's surroundings will turn black and white, and the total points that Wario obtained in that level will quickly decrease. When the total has ran out, the bomb in the Frog Switch will explode, destroying itself and forcing Wario to return to the Pyramid, losing all collected Jewel Pieces and even the Keyzer. The Vortex will then remain closed until Wario re-opens it by jumping on the Frog Switch again.

The Vortex makes a cameo appearance in Densetsu no Stafy 3, where Starfy and Wario make their way together through the Undersea Ruins. Wario is first encountered exiting out from a Vortex.