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// What if Sombra, Tirek, Chrysalis and Cozy Glow became good? 
// Story: Random MLP Questions 
// by DecoGalileo 
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Thank you for the question, MarlonCalpe4000! In this chapter, we will see what if these villains in the following reformed themselves.

King Sombra
Lord Tirek
Queen Chrysalis
Cozy Glow

So let's start with Queen Chrysalis

As we all know, Queen Chrysalis is the former queen of a big population of Changelings, and was dethroned and replaced by one of them, which was Thorax. We still remembered she first appeared, impersonating Princess Cadence, and next she appeared in an alternate timeline in which Starlight and Twilight traveled, and she returned a season later. She even made Mane 6 clones and teamed up with the Legion of Doom. We all know the scene in where Starlight wants to offer Queen Chrysalis, Starlight extends her hoof in friendship, but Chrysalis refuses and swears revenge on Starlight Glimmer before escaping. If only she agreed, she would have remained queen with Thorax, and would be one of the leaders against Neighsay due to his insults.

Next, we'll go to King Sombra, we know him as "a unicorn whose heart was black as night". Like literally every time the Mane 6 defeats him, IT WAS LITERALLY TEMPORARILY . BUT, the second episode of Season 9 was the last of him 😌. I can't find an exact answer of how he can be reformed.

Then, let's go to Tirek, and we know he is a centaur who was jealous of his good brother, Scorpan, who's a gargoyle. He just takes MAGIC to reach his strongest form. There is one tough thought when reforming him, like talk about his brother and one creature can recap and summarize how much Tirek can do than just stealing magic.

Then let's go with this psycho filly, Cozy Glow, and she clearly acts as an innocent kid throughout the series. Since her cutie mark is a rook, or the chess piece, she can manipulate others, and is like a game in a world of 64 squares, like, for example, look what she did to Chancellor Neighsay. She betrayed him, and plus, she was the one draining magic from Equestria. So, to me, I don't think she can be forgiven unless Neighsay is the main antagonist.