Doc Scratch isn't just the best villain in Homestuck, he's one of my favourite villains in everything ever. He's just so perfectly crafted on a thematic and character level.

Honestly, exploring Scratch as a manifestation of AR/Dirk//Gamzee/Caliborn/Equius souls' from Cal is an angle I don't see a lot. I think he mostly manifests as Dirk/Equius, which is interesting, seeing the qualities of characters we may theoretically like in a guy with no redeeming qualities.

@Blueberry: This is something I also really enjoy. I think another angle to take it from is that, while in the writing process Calliope is inspired by Doc Scratch, in-universe and on Caliborn/LE's timeline, Calliope existed first, which leads to the reading Scratch was spitefully crafted in Calliope's image