Rumble

Rumble is an Equestrian Pegasus colt who first appears in the My Little Pony: Friendsip is Magic season two episode Hurricane Fluttershy. He has a bluish gray coat, a two-tone dark gray mane and tail, and purple eyes. He is Thunderlane's younger brother. He is voiced by Ashleigh Ball in Season 2, then is voiced by Vincent Tong (Flash Sentry) in Season 7, possibly by getting older.

Season Two
Rumble first appears in Hurricane Fluttershy alongside his brother Thunderlane when Twilight Sparkle tests her anemometer and Spike gives a simplified explanation of what an anemometer is. When Rainbow Dash tells Thunderlane to be the first test flyer and he measures a wingpower of 9.3, Rumble gives him a look of impressed approval. Rumble appears once more before the first tornado formation attempt, informing Rainbow Dash that Thunderlane is sick with the feather flu. Season four

In Flight to the Finish, Rumble appears beside Featherweight in the stage area where the Cutie Mark Crusaders practice their Equestria Games flag carrying routine for Rainbow Dash. In Twilight Time, Rumble appears mostly off-screen during the grand opening of Pipsqueak's lemonade stand. In Inspiration Manifestation, Rumble appears with his brother Thunderlane at the Foal and Filly Fair.

Season Five
Rumble appears alongside Thunderlane at the beginning of The Cutie Map - Part 1, and at a lakeside party for Shady Daze in The One Where Pinkie Pie Knows.

Season Six
Rumble appears alongside Thunderlane in A Hearth's Warming Tail.

Season Seven
Rumble makes his first major role in Marks and Recreation, where he is afraid of getting his cutie mark and doesn't want it because he believes it limits open possibilities, and the Cutie Mark Crusaders try to get him to open up and say that they don't do such a thing, with help from his Wonderbolt brother, Thunderlane.

Role in the series
Since he changed his mind about cutie marks, Rumble has become a helpful asset, but he ends up revealing that he has another brother named Ensemble, who is like him, or was like him, but instead he's searching for a cutie mark that can allow him to do literally everything, something of which hasn't been recorded or recalled. His actions in Marks and Recreation ended up also interfering with the plans of a new threat named Cutie Marker, a supposed descendant of Beak-Buck the Cutie Mark Communist Founder, who manipulates fillies by bribing them with cutie marks, stolen or unauthentic.