ShadDash

ShadDash is the het ship between Shadow and Rainbow Dash from the Sonic the Hedgehog and My Little Pony fandoms.

Canon
As both characters come from different franchises, they have never met.

Shadow and Rainbow Dash posses great speed and sometimes use it to help others. They also use jewels as objects to increase their strength and transform into their super states. Rainbow Dash held the element of Loyalty, and Shadow is shown to be close to Maria Robotnik; something that the former understands from using the power of friendship beside her friends. Similar to how Shadow's pride has him as a "lone wolf" that isn't fond of another superspeed hedgehog, Rainbow Dash's pride has made her arrogant from time to time and had once made it her mission to unmask the mystical pony hero who stole her heroic spotlight. The two also prefer to do things alone as they use their speed to dash ahead of the others.

The dark alternate timeline of the Great Crystal War had its alternate version of Rainbow Dash going through similar things that Shadow went through in his own titled game and Sonic Forces, as well as the fact that the two have gone through other great battle related events in order to save the world. Since the two don't shy away from danger so easily, some of the ponies in Rainbow Dash's group of friends have similar personalities to Shadow's friends and allies. For example: Rarity and Rouge both have a thing for diamonds, while Rainbow Dash and Shadow aren't so keen on the two's beauty interests as they sometimes get in their way. Somewhat similar to how Rainbow Dash was tricked into becoming bad, Shadow has assisted villains before cutting ties with them later on.

Fanon
This pairing is fairly popular, only overshadowed by the Sonic-MLP crossover ships SonDash, ShadTwi, Shadshy, and ShadPie. Conversely, ShadDash is one of the crossover ships that overshadows ShadSet. It mainly has a descent size fan-base on DeviantArt than on AO3, Tumblr, and FanFiction.net; the latter which that does have a few works on the two but they mostly present Shadow and Rainbow Dash as friends than lovers as none of them has the two placed under the romantic side of the pairing. ShadDash also has a small fanbase on YouTube, where some of the videos are of other people's artwork on the ship or fan-made short films of it.

A DeviantArtist named Cyril Smith (aka Shadowthehedgehog2) used to be a fan of this ship out of many crossover ships involving the hedgehog that he has experimented with. At that time, he also paired Shadow with some of the other major My Little Pony characters. Despite this, he made multiple ShadDash fan art since 2014, and even commissioned a few artists such as SkyCircle777. Some of his art depicts Shadow as a human (à la Equestria Girls); whereas in other of his MLP-crossover ships, the hedgehog as a pony. He also wrote Shadow The Hedgehog In Equestria Girls (re-edited version), which was made into 23 parts in about a week. Cyril Smith also has a YouTube channel that has a few videos on the pairing. As of mid-2015, he has moved on from making art of this pairing to those shipping a humanized Shadow for characters in other franchises like RWBY (i.e. Yang) or Fairy Tail (Erza).

Another DeviantArtist, TheUltimateShipper42, has created a few fan art of the pairing since 2017, despite her main ships for both characters being the aforementioned ShadTwi and SonDash. One of her art depicts her pairing Rainbow Dash with at least four other non-MLP characters including Tails. Another one is a simple wallpaper and copy-pastes of official art.

Because of Shadow's stoic-like personality, fans see Rainbow Dash as the one to approach him, as well as her getting him to take down his walls or having a friendly race with, due to her need for speed. Fans tend to present themselves as either “animals”, humans or human-animal hybrids. While Rainbow Dash's personality would have Shadow compare her to Sonic, which may hinder a positive type bond, he would form with her unless puts that thought aside (like the way he sometimes puts his pride aside so he can help Sonic), so he can give her a chance. Despite the hardship Shadow has faced, he has a good heart; and a few of the friends Rainbow Dash has made in the past are ponies and creatures who have reformed.

Fandom
FAN FICTION
 * Rainbow Dash/Shadow on FanFiction.Net

DEVIANTART

Trivia

 * Similar to how Shadow's Camelot alternate reality doppelgänger was the Arthurian knight, Sir Lancelot, Rainbow Dash's “A Hearth's Warming Tail Tail” story (a MLP version of Charles Dickens’ A Christmas Carol) counterpart, Snowdash was the parody of Bob Cratchit.