Sonic Boom: Fire & Ice
Thunder Island is the seventh level in Sonic Boom: Fire & Ice. It is a small island where Dr. Eggman hosted his racing competitions against Sonic the Hedgehog in an attempt to ruin his speedy nemesis' reputation.
Thunder Island is a small desert island with cliffs, canyons and a dust-covered sky. Central to the island is a mobile Bot Racer stadium with a segmented red dome, a grey undercarriage with tracks and pipes, and a frontal bridge with an entrance gate on the right.
The inside of the racing stadium is an ever-changing circuit of technological roads with a modern, yet classic-themed starting/finishing line in blue. Along the roads are suspensions, gears, gas flasks, flaming exhaust pipes and energy fields. In the background, perpetually-moving giant gears and sawblades reside. Along the stadium's dome are also giant windows showing the outside.
Plotting to embarrass Sonic and ruin his reputation as the fastest thing alive, Dr. Eggman established a stadium on Thunder Island for Sonic to lose in against his Ragnium-powered EggBot Racers. Eggman thus took Sonic on a number of forced trips to Thunder Island, only for the hedgehog to beat his bots every time.
Thunder Island has a number of race courses designed solely for the Bot Racing minigame. Gameplay-wise, these courses are much like the adventure levels, except they are purely about speed and only include standard gimmicks like Enerbeam Swings, Boost Pads, Bounce Pads, disappearing platforms and water blocks that can be frozen or melted. This means there are no character-specific gimmicks, like dash blocks and Air Vents.
Sometimes, gimmicks like Bounce Pads are there to help the racers while others purposely serve as traps. As such, one cannot use them recklessly. Hazardous obstacles on the circuits include pits with blowtorches, red laser fields and spikes. Touching such obstacles will damage the player and return the characters to an earlier position.
Bot Racer Workshop
The Bot Racer Workshop is a workstation for Bot Racers that Tails manages. Here, the player can purchase new Bot Racers and upgrades for the playable characters using Ragnium. It becomes available after unlocking Thunder Island.
Bot Racing is the entrance to the feature of the same name. Here, the player can select from one of the unlocked Bot Racers in the game and then participate in either a single-player or two-player Bot Racing minigame. It becomes available after unlocking Thunder Island.
By collecting and assembling Trading Cards, the player can unlock additional Rival Race tracks for the Bot Racing minigame:
- Dusty Roadway: Unlocked with the Sonic Trading Card.
- Speed Demon: Unlocked with the Amy Trading Card.
- Baren Dirt Track: Unlocked with the Tails Trading Card.
- Robotic Raceway: Unlocked with the Knuckles Trading Card.
- Metallic Clash: Unlocked with the Sticks Trading Card.
- Sandhill Rush: Unlocked with the D-Fekt Trading Card.
- Thunder Island is the first case in the Sonic franchise where the last level in the game (albeit not an optional one) can be accessed without going through all the levels preceding it.