The Diamond Dogs

The Diamond Dogs (Rover, Spot and Fido) are a trio of said dogs from Equestria and characters from The FT Squad's Adventures in My Little Pony: Friendship is Magic. They are gem hunters and are always on the lookout for shiny gems and jewels. At one point, they abducted Rarity upon witnessing her good talent in looking for gems with Spike. But this backfired on them when Rarity was constantly complaining about them and the underground cave they were in. After much whining, complaining, and even crying, Rarity finally pushed the dogs to the edge and they let her go, right when Rarity's friends came to rescue her.

TRIVIA

 * The Diamond Dogs will appear as minor villains in The FT Squad's Adventures in My Little Pony: Friendship is Magic, but won't bother the heroes after they release Rarity.
 * Kylgrv thinks the Diamond Dogs resemble Shenzi, Banzai and Ed from The Lion King.