The Villains

Vs. Twilight

Garland: Friendship has no meaning in battle!

Emperor Mateus: An iron fist is all a ruler needs.

Cloud of Darkness: Your nightmares give us strength.

Golbez: I will show you exactly what I have learned.

Exdeath: Friendship cannot survive the Void!

Kefka: What have we here? A walking, talking self-help booklet!

Sephiroth: Your faith in your friends is your greatest weakness.

Ultimecia: Your ideals have no place in my time.

Kuja: Do you ever shut up about friendship?!

Jecht: Geez, you like to talk about makin' friends, don't ya?

Chaos: The magic of friendship... cannot overcome Chaos.

Vs. Rainbow Dash

Garland: Don't get cocky, foolish one.

Emperor Mateus: You ARE the reckless type, I see.

Cloud of Darkness: Your brashness will be your downfall.

Golbez: Do not get ahead of yourself.

Exdeath: Your impatience is intolerable.

Kefka: Woo-hoo! You've got spirit.

Sephiroth: The recklessness of youth.

Ultimecia: Your boasting is a waste of time.

Kuja: Quite the narcissist, aren't you?

Jecht: Please. There's no one better than me!

Chaos: Your arrogance... will be your undoing.

Vs. Applejack

Garland: Are you strong enough to break me?

Emperor Mateus: Honesty has no place in my Empire.

Cloud of Darkness: You are no more than a speck of light.

Golbez: Let me see your resolve.

Exdeath: Your strength cannot defeat me, pony!

Kefka: How do you like them apples?

Sephiroth: A worthy challenge, to be sure.

Ultimecia: Not even your family is safe from the flow of time.

Kuja: That accent is just annoying.

Jecht: Well, let's this over with, cowgirl.

Chaos: Your strength alone... is nothing.

Vs. Fluttershy

Garland: Only cowards die in battle.

Emperor Mateus: All forms of kindness must be eliminated.

Cloud of Darkness: We sense much fear in you, little pony.

Golbez: I am afraid there is no other way.

Exdeath: I see the fear in your eyes.

Kefka: *cackling* Fraidy cat! Fraidy cat!

Sephiroth: Is there any courage in you at all?

Ultimecia: You should stay where you belong, little girl.

Kuja: *laughs* Such a weakling!

Jecht: *scoffs* You're just a kid.

Chaos: You are no more than a coward.

Vs. Pinkie Pie

Garland: I'll seal your mouth shut once and for all!

Emperor Mateus: Do you not know the meaning of the word "silence?"

Cloud of Darkness: Talkative, aren't you?

Golbez: What do you mean by, "Allez cuisine?"

Exdeath: You and that fool would go along nicely...

Kefka: I thought you were the Element of Laughter... Oh well, too bad!

Sephiroth: Do you ever keep quiet?

Ultimecia: Hmph. I've no time for the likes of you.

Kuja: Do you ever shut up?!

Jecht: You sure like to talk, don't ya?

Chaos: Cease your nonsensical rambling, mortal.

Vs. Rarity

Garland: You'll be lucky if you leave with only a few scars.

Emperor Mateus: "Generosity?" What is the meaning of that word?

Cloud of Darkness: The Void has no use for generosity.

Golbez: If there is light within...

Exdeath: In the Void, no one can hear you scream.

Kefka: Hoo hoo hoo hoo hoo. Another plaything just for me!

Sephiroth: I wonder if you can even fight without magic.

Ultimecia: Such a vain creature...

Kuja: My, aren't we pretentious?

Jecht: I'm not goin' easy on ya, lady.

Chaos: Generosity? Or vanity? Which is your greatest trait?

Vs. Spike

Garland: This will be quick.

Emperor Mateus: This is my opponent? What a joke.

Cloud of Darkness: A little one like you has no chance against us.

Golbez: Let us see if appearances can be deceiving.

Exdeath: I'll step on you like an ant!

Kefka: Keep practicing, lizard boy!

Sephiroth: Your "idol" is no more than a puppet.

Ultimecia: *sigh* Very well.

Kuja: My Silver Dragon could crush you in an instant.

Jecht: Stay outta this, kid.

Chaos: Nothing more than an insignificant weakling.

Curious what the lone with Pinkie and Golbez refers to. I'm also honestly curious what the Mane 6 would say to the heroes even if they are on good terms.

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Fun fact: Golbez's Japanese voice actor, Takeshi Kaga, played the role of chairman on the cooking show, Iron Chef.

Ohh~ Had no idea it was him

Now it got me thinking how Comos side say to Mane 6 and spike? and same way Mane 6 and Spike at Cosmos?

The Heroes

Vs. Twilight

Warrior of Light: Your faith in friendship is commendable.

Firion: I guess we don't have a choice.

Luneth/Onion Knight: Me? Fighting a princess?

Cecil: You truly deserve your title.

Bartz: The more you think, the less time for action.

Terra: I'm glad I can call you a friend...

Cloud: I'm not interested in reading.

Squall: Princess of Friendship? Whatever.

Zidane: You seem like an out-going lady.

Tidus: You definitely need some fun in your live.

Vs. Rainbow Dash

Warrior of Light: You're skilled, but you're also very reckless.

Firion: How can anypony be so cocky?

Luneth/Onion Knight: C'mon, Rainbow Dash. Let's do this!

Cecil: Never act before thinking.

Bartz: Let's have some fun.

Terra: If only I had some of that energy.

Cloud: Need to control yourself.

Squall: Not another loud one.

Zidane: Alright, let's go!

Tidus: Time for some action.

Vs. Applejack

Warrior of Light: Your honesty... is your greatest strength.

Firion: Let's see how strong you really are.

Luneth/Onion Knight: What kind of job suits you more?

Cecil: To have faith in your friends.

Bartz: You use those back legs of yours for bucking apple trees? Really?

Terra: Do you know what love is?

Cloud: How powerful can one little pony be?

Squall: *scoffs*

Zidane: Will you stop lecturing me?

Tidus: You seem a bit uptight.

Vs. Fluttershy

Warrior of Light: There is a hidden strength within you.

Firion: Show me your courage, Fluttershy.

Luneth/Onion Knight: C'mon. Don't be scared.

Cecil: Never give in to your fears.

Bartz: You need to relax and enjoy life.

Terra: Please don't be afraid.

Cloud: You've got something inside you. Now let it out.

Squall: Finally, someone less talkative.

Zidane: You've gotta open yourself up to people, y'know?

Tidus: Guess I know why "shy" is part of your name.

Vs. Pinkie Pie

Warrior of Light: You need to control yourself sometimes.

Firion: The world may need someone like you.

Luneth/Onion Knight: How come you're so bubbly?

Cecil: Out of curiosity... What are you, really?

Bartz: Glad I could make a new friend.

Terra: So much happiness.

Cloud: Not interested.

Squall: You're just as hyper as Zell and Selphie.

Zidane: Someone's had some sugar.

Tidus: Don't you ever tire yourself out?

Vs. Rarity

Warrior of Light: A heart worthy of the light.

Firion: Think you can fight?

Luneth/Onion Knight: Just do your best, Rarity!

Cecil: I want to know if you have the resolve.

Bartz: Sorry, but can you not shout next time?

Terra: I'm sorry about all this.

Cloud: Do you think you can heal all our wounds?

Squall: A generous pony? Whatever.

Zidane: You know something, Rarity? You're so prissy.

Tidus: Come on. You need to have some fun in your life!

Vs. Spike

Warrior of Light: This will not be an easy fight.

Firion: Show me what you're made of, Spike.

Luneth/Onion Knight: No sense making me wait. Let's go.

Cecil: Alright. Let's begin.

Bartz: Let's prove you're not a lame dragon.

Terra: Do we really have to do this?

Cloud: I won't go easy on you.

Squall: Big things do come in small packages.

Zidane: C'mon, Spike.

Tidus: Ready for a blitzball lesson?

Gives me a good me a good idea who all Bartz is going to click with. Terra seems to generally like everyone, which is expected. I can imagine ponies alone would get a similar reaction as Moogles do with her.