Sonic Spinball is a pinball video game developed by Sega Technical Institute and published by Sega. In the game, players control Sonic, who must stop Doctor Robotnik from enslaving the population in a giant pinball-like mechanism. The game is set in a series of pinball machine-like environments, and Sonic acts as a pinball for the majority of the game.
The game was developed by the American staff of Sega Technical Institute, as the Japanese staff was occupied with developing Sonic the Hedgehog 3 and Sonic & Knuckles. When Sega management realized that Sonic 3 would not be completed in time for the 1993 holiday shopping season, they commissioned another Sonic game that would be. The game was hastily designed amid time constraints, with most work taking place over two months. Sonic Spinball was released for the Sega Genesis in November 1993, and for the Wii Virtual Console in 2007.
Sonic Spinball is a pinball game in which the player controls Sonic the Hedgehog, who acts as the pinball. The majority of the game takes place within the "Pinball Defense System", which resembles a series of large pinball machines. The game comprises four levels, each containing numerous flippers that can be used to aim Sonic's trajectory and launch him through the level. Sonic can be maneuvered while airborne with input from the directional pad, which can be used for better positioning following an impact with a bumper or target or when Sonic is descending toward the drain, bumpers or flippers.
The goal of each level is to collect all of the Chaos Emeralds and subsequently defeat the newly accessible boss located at the top of the level. Some Chaos Emeralds are blocked off by obstacles that require Sonic to hit certain switches or bumpers in order to create a clear path. The boss at the top of each level requires a specific strategy to defeat. A "status strip" at the top of the screen provides hints for defeating bosses as well as encouraging messages when the player makes progress. The strip also tells the player how many Chaos Emeralds are left to collect in a level. Following the defeat of a boss enemy, a bonus round is initiated. These rounds are shown as Sonic playing a regular pinball machine. The player is given three balls to shoot around the board, the object being to accumulate points by hitting as many bumpers and targets as possible. At any point in the bonus round, the player may trigger a tilt shake that rattles the table and affects the ball's trajectory. If the tilt shake is used too often, however, all flippers will lock out, leaving the ball to fall down the drain. When the goal of the bonus round is fulfilled, or if all three balls fall through the flippers, the bonus round will end, and the next level will commence. When all of the game's Chaos Emeralds are collected and all four boss enemies are defeated, the player wins.
Sonic starts the game with three lives. A life is lost when Sonic falls through a drain. An extra life can be earned by accumulating 20,000,000 points, which can be accumulated by hitting bumpers, navigating through loops, collecting rings and destroying enemy characters.
Dr. Robotnik has assumed control of Mt. Mobius on Planet Mobius and turned it into a mechanical base. Utilizing energy produced by the magma flowing under the volcano, this new monstrosity base (the Veg-O-Fortress) has the power to transform helpless animals into robot slaves at an astounding rate. Sonic the Hedgehog and Miles "Tails" Prower fly onto the scene to mount an aerial assault, but Sonic is knocked off the wings of Tails' airplane by a blast from the fortress. He falls into the water, but is rescued and taken to the subterranean levels of the Veg-O-Fortress. The fortress must be destroyed from the inside-out, and the only way to make that happen is to trigger an eruption in the volcano it's built on. Sonic knows this can be done by removing the Chaos Emeralds that keep the volcano stable. Dr. Robotnik, however, is also aware of the fragile relationship that exists between the Emeralds and the mountain, and he has established an elaborate Pinball Defense System to make sure the precious jewels don't go anywhere.