The pre-scratch trolls session had a glitch in it because they weren’t spawned in their session which is one of the reasons they had to scratch. John’s session didn’t have a glitch and he created all 8 human kids via ectobiology. This is why Jane didn’t have to do ectobiology for her team mates. 

Bro is the result of leaving someone with manipulation issues like Dirk’s left unchecked and also living since birth with an evil puppet like Lil Cal which has the soul of Caliborn inside it. I’m not trying to attribute all of Bro’s abusive tendencies on Lil Cal but I think they were definitely accentuated by Lil Cal’s presence.

The page was uploaded 4/16/09 so yes, way before Roxy was introduced. 

Yes. 

John was the leader of the betas, Roxy was the leader of the alphas, Karkat was the leader of the post-scratch trolls, and Meenah was the leader of the pre-scratch trolls.

“The Witch of Time was not always the party’s 8iggest trou8lemaker. […] Once she was as meek as can 8e. Hailing from the eastern provinces, she migrated across the seas and settled near the forest concealing Rufioh’s guild. The two of them 8ecame quite fond of each other, and shared many interests! He secretly 8egan seeing someone else, 8elieving she knew nothing. 8ut she always suspected his infidelity, and over time grew quite distraught. 8ut her sadness never quite turned to rage and malevolence. Not until you… involved yourself.” 

He cheated on her with Horruss.

that aranea on page 6669 said she was terezis ancestor in a way. but its kinda confusing so idk

When Aranea said that she meant in terms of that she predates them as her next lines are 

“[Vriska] had an ancestor whom she was aware of, and technically that is who I am.  That is to say, she is who I would have 8ecome on your world, had I arrived in her place. Alas, I did not. She was a figure in your history who preceded you 8y thousands of solar sweeps. Whereas I preceded your entire civilization 8y 8illions. ”

No

The fact that Karkat didn’t know who the extra 12 were proves that Karkat’s group is the parent generation. Because if they were the parent generation Karkat would have seen them on the screen when he had to clone them and get their ecto-goo for mixing. And actually if we based it off how the kids’ worked then the Alpha trolls would be the children generation since the human’s child generation played the game first.