Signless and the Disciple’s relationship expanded beyond the quadrants.

Mindfang and Dualscar were black but broke up

Mindfang and the Summoner were red 

Mindfang was red with a female slave that might have been Dolorosa but that’s not confirmed.

http://forgottenhsfacts.tumblr.com/post/116068357635/tavros-is-allergic-to-cats-source 

No, their corpses are far too old and mangled

Jake’s grandma took the name English to spite the Condesce and Jake got it from her.  Jane’s Poppop’s original last name was Crocker, and due to tradition he did not change it when he supposedly got married at some point.

Grandpa Harley took the name Harley after his beloved dog Halley that he pronounce wrong due to a speech impediment.  Nanna’s original last name was also Crocker but she supposedly got married at some point and changed it.

I wouldn’t say he’s evil, but he’s not good either. ANd yes he has the felt with him

Here

He’s a bad dude but not in the way that the other bad guys are.  He doesn’t have anything against the kids and he was Karkat’s exile so he might join them to the fight against the other Jacks.

I dunno, after Act three everything gets longer and more flash heavy.  I’m not sure how he’d put Cascade into book format.

Oh boy okay, here we go.

Condesce: Trolls are off limits here since she can control them so I’m guessing John and Roxy as they could both easily dodge her attacks (John by turning into Breath and Roxy by turning intangible), maybe Dirk when he shows up.

Spades Slick: Karkat due to his past relationship with Slick and Jake cause he’s not in the right mental place to get into a serious rumble right now.

For the Dogs: Rose and Tavrosprite.  Tavrosprite may be able to commune with them using his psychic abilities and Rose using her advanced Seer powers would likely be able to predict teleporting.  Again though, like Vriska said, PM wants to beat up Bec Noir so Tavros and Rose might just be there to assist.  Maybe bring the Mayor too, idk.

Jack English: This guy needs tough fighters to brawl with him so  Dave, Terezi and Kanaya, maybe Dirk when he shows up, I’m not sure where to put him.

Jane will obviously be hopping  all over the place, and I feel like Arquius will stick with her to provide protection.  If not, I’d give him to Jack English because who’s tougher the Arquius?

I think Jaspersprite will stay with Jade because if Jade wakes he could instigate her into chasing him again and keeping her away from the Condesce.

This is all speculation, and I’ll probably end up being way off, but who knows

It’s Biscuit’s juju.  Spades Slick got it when he gathered the Felt and started leading them.