The Super Mario Silver Spurs Saga is a series of crossover films and games created by Lone Planet Productions.
After the events of Super Mario 3D Land, Mario falls through a hole in space-time and comes across Sonic the Hedgehog and Finn the Human, who have done the same after Sonic Generations and Adventure Time: HIK!WYSOG?!, respectively. The three unite when Bowser, Dr. Eggman, and the Ice King spread their forces between worlds.
The first addition of the franchise. After over 25 years of rescuing Princess Peach from Bowser's clutches, Mario is getting bored of doing the same thing over and over again. Thus, he sets up a vacation across the universe with his brother Luigi. Their first destination is Brooklyn, New York, but a wierd-looking spacecraft shoots them down, sending them plummeting into Elmore instead. There, Mario meets Gumball Watterson, and a slight annoyance with him develops. But when a dark enemy threatens the meta-universe, the two must join forces to stop him, with the help of other heroes, like Sonic, Finn, and Kirby.
After Mephiles the Dark is seemingly trapped in the Void, Count Bleck uses the Dark Star to create a doppleganger of Mario who then spreads disaster around the Mushroom Kingdom. Mario is sent to jail, but Sonic and Gumball break him out, and Rosalina assigns them with their first official mission: to locate a mysterious new Chaos Emerald known as the Eclipse Emerald. With this Emerald, the three of them can reverse the effects of the Dark Star.
In a mad pursuit of meta-universal domination, Mandy creates a device that can rip a hole into The End's atmosphere, allowing the energy within it to collapse into the real world. She sends the Ender Dragon to blast Mario into the 2nd Dimension, an alternate universe in which many things have changed -- the main focus being that Mario doesn't exist in this universe. He desperately attempts to escape the 2nd Dimension, with assistance from the timeline's counterparts of Luigi and Tails. Meanwhile, Mandy has a menacing surprise waiting for our hero...
Mandy escapes from the G.U.N. Interuniversal Prison and gathers a group of villains to tamper with reality. Mandy offers Nergal Jr. the Eclipse Emerald as a reward for eliminating Mario.
Two years after the events of Dimenional Duos, the multiverse is at war. Sonic has split away from the Guardians, forming his own squad of "heroes" who seek to create a new government. Mario and company is pitted against Sonic's team, as well as several others, including the return of Koopa Kid.
After Gumball is cryogenically frozen to "prepare him for the future" and heal his wounds, Mario desperately attempts to piece the republic back together as he loses more and more allies. But Wart seeks to stop him by all means available, for the sake of his mysterious "boss".
These three versions of a spin-off game revolve around Mario (in Red), Dexter (in White), and Sonic (in Blue). Mario searches across the multiverse for hints of the upcoming apocalypse mentioned in Rosalina's prophecy; Dexter wants to overthrow the Ice Climbers, the leaders of the Lower Vigilantes, so he can lead them to "pure success"; and Sonic is still trying to get over the loss of his faction.
In this conclusion to the series, the apocalypse arrives in the form of an attack from the dark Lady Azul, who transforms any creature she can get her hands on into a monster. The story is told from the perspectives of Mario, Sonic, Bowser, and Gumball, who has been released from cryogenic slumber ten years into the future by his brother Darwin. Deep within these events, Mandy and her allies prepare for the devastating revival of Mephiles.