she then bites his finger

Spike: Alright, Discord. I’ll just never let you live it down that you betray us for the devil himself which broke Fluttershy’s heart, nearly sent a mare into another dimension out of petty jealous for Fluttershy’s attention, and nearly destroy us when the vines attack just for “shits and giggles”  
Discord: Oh I see, when I do something chaotic, it’s all “Discord, stop doing! You’re out of control!” But when a baby does it, it’s all “she didn’t mean to!”  
Spike: Yeah, so what’s exactly your excuse? Unless you wanna swap titles, she could be the lord of chaos, while you be the big baby.  
Discord: …I really hate you.

@Evowizard25  
Actually, since she wasn’t alive then, it’s not likely that she’d remember it at all.

@A-T-S  
Or, being the trickster mentor that the reformed Discord is, he’d do both; He’d remind her of almost destroying stuff, guiding her toward caution, but he’d pretend to be upset she didn’t do a better job.

Knowing Discord the part he’s not gonna let her live down is the “almost” bit.

she will destroy him

And she won’t ever let you forget the time you betrayed Fluttershy and doomed to Equestria.  
It’s a two way street, pal. :)

“I’ve already taught her how to knock planets out of orbit!”

Probably help you do it a few times.
 
Maybe even lengthen your name.