@KSLDRDPL  
Well, the last time we see Grubber is that he warned the Storm Creatures to attack the Mane 5, Spike, Capper, Captain Celaeno and her pirate crew, and Princess Skystar after he tries to eat a whole cake that Skystar, Celaeno, and her pirate crew were inside but gets captured as he does so. After Skystar, Celaeno, and her pirate crew burst out of the cake, Grubber was last seen sitting down with his hair sticking out covered with icing and he was never seen again until the ending credits. In “The Great Princess Caper”, Grubber was unable to fight the Mane 6, Spike, Capper, Captain Celaeno and her pirate crew, and Princess Skystar with no avail and hide himself for the rest of the film. After the Storm King died, his army defeated along with him, Tempest, Derpy, and the first three princesses de-petrified, the magic restored back to Equestria, Equestria is fully repaired and restored back to normal, and all of the inhabitants across Equestria are free from the Storm King’s evil reign, punishment, slavery, captivity, darkness, and control, Grubber believes he’s completely ignored by Equestria and decides to leave and return back to the Storm King’s abandoned castle southwest of Equestria. But Tempest runs up to him and makes amends with him by giving him a cupcake with the word, “sidekick”, which puzzles him, reminding her that she was doing something evil and he and Tempest aren’t evil anymore. Tempest explains that while Grubber failed to be evil, powerful, mean, and scary like the rest of the Storm King’s soldiers, he still proved to be generous, loyal and laughable and she wants him to be her friend. Grubber happily accepts and joins the Friendship Festival playing karaoke with his microphone that he used in the beginning of the film, pulling up the piñata shape of the Storm King when Tempest was trying to wack it blind fold (only for her to take it off and blast it with her magic), dancing with the rest of the film’ new characters and Twilight’s friends, and befriending Spike.

You forgot the worst of them all. Spoiled Rich.

@Background Pony #EBBD
 
When did Grubber reformed? And I don’t think helping save equestria from doom is considered reforming for conman like F&F.
 
 
@Red-Supernova
 
Why not? I don’t consider her really evil but she was pretty antagonistic in her episodes.

I really don’t consider Lightning Dust an antagonist at all.

@Background Pony #EBBD  
Yeah, but we never got to see where their new lives take them. I don’t mind that, though, since it lets us have more fun with our imaginations and we’re free to guess and come up with our own ideas.

You still know that Garble, Flim and Flam, Grubber, and Chancellor Neighsay are reformed. While the rest aren’t. Right?

The Maneiac was always a favorite of mine.