Darkkaraszero
Biker Mice from Mars × SWAT Kats: The Radical Squadron
When Limburger's dimensional gateway goes haywire, Throttle, Modo, Vinnie, and Charley crash into Megakat City-a world of cats, towering skyscrapers, and two vigilante pilots who aren't expecting motorcycle-riding mice.
But the mice aren't the only visitors. Limburger has found a dangerous new partner in Dark Kat, and together they plan to strip Megakat City of its resources. To stop them, the Biker Mice and SWAT Kats must combine Martian muscle, mechanical ingenuity, and the firepower of the Turbokat.
Engines roar, missiles fly, and an unlikely friendship takes shape. Yet beyond the battle, a mysterious transmission from Mars could lead them toward an even greater adventure.
An action-packed crossover one-shot with an open ending.
Reader continuation welcome: Anyone may continue or adapt this storyline into their own fanfiction, adding their own adventures, characters, and ending. Credit to this starting story is appreciated. The original franchises and their characters belong to their respective owners.