Training Tails

Training Tails is a Sonic the Hedgehog fanfic by Stainless Steel Fox, set in the Sonic Sat AM continuity. As the name indicates, the fic focuses on Miles 'Tails' Prower and his personal journey to train himself to become a more valuable member of the Freedom Fighters.

How does he do this? After an attempt to take down Robotnik's latest plan all by himself goes awry, Tails ends up getting inadvertently transported into the Dragon Ball universe by an interdimensional portal. There, he meets up with Goku, and together they undergo a crapload lot of Training from Hell. The two-tailed fox ends up taking several levels in badass and becomes significantly more powerful and intelligent. As his adventure goes on from there, however, he realizes he has much more to learn beyond just kicking ass and taking names.

The first part of the fic is a crossover with the manga version of Dragon Ball, while later stages will be a crossover with the Star Fox universe.

Tropes used in Training Tails include:

Awesomeness By Analysis: One of the most defining traits of this depiction of Tails, such as being able to calculate trajectories on the fly before deciding on how to throw objects.
Badass Bookworm: Tails, very much so after his training under Master Roshi.
Cold-Blooded Torture: In Chapter 23, during a fight with Tien Shin Han, Tails gets overwhelmed, and ends up getting his tails forcibly ripped off his butt. Only by taking a magical Senzu Bean given to him by Goku earlier is he able to regenerate them instantly and get back up.
Crossover
Curb Stomp Battle: Most of the Red Ribbon Army stand pretty much zero chance against Tails or Goku in a fight, though it does get gradually harder for the duo.
Goggles Do Something Unusual: Tails' goggles are one of the most useful gadgets he has, having a whole host of features such as nightvision, blocking out the moon (for the pair given to Goku to prevent his transformation into a Great Ape), detecting enemies, detecting dragon balls, etc.
Hard Work Montage: While building the Sea Fox, set to the MacGyver theme song no less.
How We Got Here: The second chapter already shows Tails returning to Mobius after completing his training, and the entire fic from there shows everything he had gone through and experienced within six years.
Idiot Hero: Goku, much like in the canon.
Tail Slap: The Tailspin attack is an Up to Eleven version of this.
Training Montage: Chapter 5.
Techno Babble: Tails being a technical genius and the author being a big sci-fi fan and actual engineer by profession, this comes from the fox a lot.
Thou Shalt Not Kill: Tails tries to hold onto this principle as hard as he can, but comes to realize it's really not that easy in the Dragon Ball world after encountering the Red Ribbon Army. Notably, it actually led to Tien getting an advantage over him in the fight mentioned above, as Tails did not use lethal force when he could have.
Year Inside, Hour Outside: Six years pass for Tails while only an hour passes for the rest of the Freedom Fighters on Mobius.