Nightmare Moon - Yami Marik  
Discord - Pegasus  
Former Queen Chrysalis - Dartz  
Lord Tirek - Zorc  
Cozy Glow - Noah Kaiba

Zorc and Sombra are not pure evil. They were rejected from the villains wiki so they are not pure evil. Get your facts straight.

@CannonFodder  
CARD GAMES ON MOTORCYCLES!

Nightmare Moon: GARBAGE DAY…
 
Cozy Glow: Princess Luna?
 
Nightmare Moon: Hey Cozy how’s it hangin? Get it cause you’re gonna die. Eh I guess ya had to be there.

The way I set it up was:
 
Discord = Pegasus (villain who loves childish things and is basically totally unpredictable, ultimately ends up helping the heroes)
 
Marik = Pinkamena (evil, corrupt version of an essentially good character)
 
Noah = Diamond Tiara (not so much a villain as just sort of a spoiled brat)
 
Chrysalis = Dartz (same reasons you stated above: royalty harvesting mental/spiritual energy)
 
Tirek = Zorc (basically a demon; overpowers all forces used to defeat previous villains)

@Psyga315  
Nightmare Moon should be like…  
“[Hallowen theme song] Hey, sister! You took my subjects’s love, so I took your bodyguards’ kidneys. I believe that’s a fair trade.”

Have some chocolate rain, binky boy!

You, sir below me, won the Internet.

Oh. Dear. God.
 
Nightmare Moon: My Little Pony is filmed before a live studio audience.  
Discord: Come give Florance a hug!  
Chrysalis: I’m gonna take Shining Armor’s DEEEEECK!  
Bakura: Sombra, why aren’t you destroying the world?  
Sombra: I have a terminal disease!

So…Sombra is going to have a giant dragon head for a penis then?

er what….sorry but some of these comparisons don’t work
 
they should be switched around if anything

well, because his body was destroyed and now he is just a big shadow thing, i think king sombra will not have spoken role.

(…and other fans, i believe)

vv Dartz and Zork (True form of Yami Bakura, since my point of view)

CARD GAMES ON MOTORSCYCLES!

I am not familiar with the last two on the right.

So… I should probably run if Discord asks for a hug.
 
Ok, got it.