It all starts when Sonic finds a badly injured fox kid in a forest. Soon, one thing leads to another, and he's in a chase after Dr. Robotnik, who seems to have an even bigger scheme than last time. With new friends and strange events spiraling beyond his control, Sonic's got a lot on his plate, with the newly-named "Tails" along for the ride.

AU, collab with my sister. Mario and Luigi were just normal adventurers, apart from the fact that they were of the rare human race. One day, by a chance encounter, they find out why humans are so rare - And, with a new compainion in the Princess of the kingdom, set out on their biggest adventure ever.

It's an indisputable fact of the universe that Mario Bros plus Vacations equals Evil Plots to foil. Sonic and Tails get into trouble just as much. So, when the Bros go on a vacation to Pi'illo Island, it doesn't take long for a new, world-threatening evil to be unleashed, and for a new adventure to begin.

When you've got two groups of super powerful people, things can get a little weird. Even more so if half of them are children, and the other half acts like it. Random, stand-alone, short stories about the Mario and Sonic cast.

Two heroes, from very different places, happen to take a vacation to the same place at the same time. Being Mario and Sonic, the vacation goes south almost immediately, and they're thrown into another adventure with the fate of the world at stake. (Loose retelling of Sonic 2006 with Mario characters)