Lightning Dust

Lightning Dust is a female Pegasus pony character who appears in the episode Wonderbolts Academy. She shares her eye color and sometimes her cutie mark with Sassaflash, whose coat color is very similar to hers. Lightning Dust's cutie mark consists of a lightning bolt and three stars. She is also the only Pegasus Pony shown in the series to leave behind some kind of stream when she flies, while Rainbow Dash stream is a rainbow, Lightning Dust is a thunder bolt.

Depiction in the series
Lightning Dust is shown to be a vigorous and highly competitive flyer who loves to test her limits over what she can or cannot accomplish. With her strong attitude, her speed, and love for flying, she quickly forms a friendship with Rainbow Dash. However, because of her competitive spirit, Lightning Dust is also very reckless and shows little concern for anyone that becomes a victim of her actions. This is shown when she ignores Rainbow Dash's injury caused by her knocking her wing during a team exercise, or when she brushes off the fact that a tornado she caused flung Rainbow Dash's friends from Twilight Sparkle's hot-air balloon, endangering them. Lightning Dust's recklessness and disregard for the well-being of others causes Spitfire to take away her team leader pin and give it to Rainbow Dash.

Quotes
"Let me show you what I've got, ma'am."

- Wonderbolts Academy

"Ma'am, can you put the Dizzitron on maximum speed? I wanna push my limits."

- Wonderbolts Academy

"They should make us Wonderbolts right now."

- Wonderbolts Academy

"Hey, you snooze, you lose! Besides, Wonderbolts are supposed to be able to recover from a spinout. You saw them on the Dizzitron. They could use the practice. I mean, it's not our fault we're so much better than those other guys. Not every pony is destined to become a Wonderbolt. Only the best of the best, right?"

- Wonderbolts Academy