(Assuming it's the same guy who flagged the Amy sequence) First the false flagging of the Amy sequence, then he does the same thing to the informational posts explaining what happened, and now this?

I doubt it isn't the same guy though. It being the same guy is the most likely possibility.

With that in mind I ask, how spiteful can one troll be?

This also seems like an attempt to prevent you from getting any future commission clients. We need to show him that it won't work.

We have an IMPOSTOR Among Us.

What did you do to piss this guy off to this extent to them flagging your stuff on Deviantart, and then going full on mudslinger on BBWchan?

Do trolls like this even need a motivation?