Radical Train

Radical Train is an Action Stage in Sonic the Hedgehog (2006). It appears to be a terminal station for Soleanna. It appears in each character's story at the same exact time with each character having their own intentions. Sonic's and Shadow's stages involve a race against a train to either save or destroy it (respectively). Silver's version of the level does not involve the train.

Sonic
After ﬁghting his way back from a future destroyed by the diabolical Iblis, Sonic now sets his sights on Dr. Eggman. However, the madman has created the perfect diversion to keep Sonic off his back while he attempts an escape: a runaway locomotive full of innocent passengers. As much as Sonic wants a showdown with Eggman, he can’t just abandon the people on the Dr. Eggman's Train, so he diverts his course to clear the stretch of track that Eggman has sabotaged. After Sonic saves the train, he can then chase down Eggman’s own locomotive before it can outpace even the world’s fastest hedgehog.

Sonic is on a mission to save the princess and therefore he is tied with time and because of this the player must  hurry and activates the switches to save the train from being damaged. The slow Gem is useful for the Hard mode of Sonic's level to make the mission more easier than before.

Silver
Sonic may have needed to chase down a runaway locomotive while escaping Dr. Eggman’s taunts, but when Silver visits the mountainous train yard, he has to ﬁght through an army of aggressive robots and outthink a series of clever crane puzzles that block his path. The trains do indeed make an appearance, but these locomotives run on schedule, giving Silver ample opportunity to avoid getting smashed and maybe even use the engine to pick up some treasure he can’t even reach with his psychic powers.

Silver's version of the level is harder than the two and has more enemies. Silver is not tied with time as his mission is not to catch Eggman and therefore, the player is free to take his/her time.

Shadow
Shadow The Hedgehog follows Dr. Eggman to a mountaintop train line, where rails curve around lofty peaks and a false step could lead to a long, unpleasant descent. Eggman’s locomotive has a head start on the hedgehog, so he must beat feet parallel to the track and slow the train with a series of laser ﬁelds. Eggman, seeing the threat, sends his robot army to keep Shadow busy while his train picks up speed. Shadow does not possess Sonic’s gift of speed, so he must rely on his motorcycle to close the gap and destroy the train before it escapes into the treacherous mountain pass.

Shadow's version of the stage is slightly harder than Sonic's. This version has more robots and Egg Launcher in it and instead from saving the train Shadow has to attack it to talk to Eggman. Shadow's final section of the level is the similar to Sonic's but instead of running at high speed Shadow will ride a motorcycle to attack the train.

Trivia

 * Radical Train and Aquatic Base are the only levels not to appear in End of the World.
 * This level is not used in Tag mode.
 * The freight locomotives in this level are based off the American EMD SD70M, and the red passenger train is not based off a specific prototype, however it does bear a resemblance to generic European multiple-unit trains.
 * The music in this level seems to be a remix of Crisis City's "Tornado" music.
 * Radical Train is the only level where all three male hedgehogs are in at the same time.
 * It is also the only level to be the same number for all 3.