Rainbow Dash is a multi-colored Pegasus from Cloudsdale, and the main reason behind the Sonic Rainboom, and getting all her friends their Cutie Marks. She is also one of the Elements of Harmony, representing the Element of Loyalty.
Rainbow Dash is at average height for a Pony her age. She has light blue fur and feathers, and her mane and tail are tomboyish in appearance, multi-colored like Bismuth, with similar colors. Her wings are pointed and described similar in shape to a Peraguin Falcon. Her Cutie Mark consisted of a multi-colored lightning bolt coming out of a storm cloud.
Rainbow Dash is the most action-orientated, and most aggresive of the Mane Six, more than willing to lock horns and hooves with other adversaries in a fight whenever one does present itself. She will stand up for others weaker than herself, often starting up something if she finds someone else in trouble. She will even go on missions alone if it meant to help her friends, notable when she decided to follow and track Peridot on her first visit to Earth.
As the element implies, she is very loyal to her friends and doesn't truly consider herself the type to backstab anyone, picking a side and sticking with it thick and thin. With her aggresiveness however, this also makes her little fan of relaxation, and finds enjoyment in fighting more so than some would enjoy. This is often shown up during the missions she's on, a good example being during her trip in Darastrix, her saying she was hoping for a monster behind the problem, as it would be awesome to fight one.
Her life isn't completely about fighting however, as she does hold some less action-oriented traits, such as her being a hardcore fan of the Daring Do books, a series she's very passionate about, and she is shown fan-girling over meeting A.K. Yearling. Her passion is also extended to the Wonderbolts flying team, someone she especially idolizes, and went to the Wonderbolt Academy alongside April Showers and Sunshower Raindrops with the same passion in mind.
Enhanced flight speed
The ability that earned her Cutie Mark, She is able to fly fast enough to perform a legendary move known as the Sonic Rainboom. It was this same move that not only got her cutie mark, but everyone of her other friends' cutie marks as well.