When you die, you wake up as a ghost in a dream bubble. The dream bubble’s environment can change according to the memories of the ghosts in the bubble. 

The meteors flying at Skaia is called the Reckoning and it’s initiated once the Black king and his army defeat the Prosptians. Depending on how many players there are, yes the Reckoning could happen at different times in different sessions. The Beta kids’ Reckoning happened early because Jack Noir killed both kings and started it before the war was over. 

The dream self only becomes a godtier if your main body dies on your Quest Bed. If your dream self dies then you can still use your Sacrificial Slab at the center of the moons of Derse or Prospit to ascend. Calliope’s dream self was killed and she never came back because Caliborn took over the body. Karkat’s dream self died and he has no way to go godtier because both his Quest Bed and Sacrificial Slab were destroyed by Bec Noir. 

I’m pretty sure those are tights.

Post scratch Earth got sucked into the black hole in [S] Caliborn: Enter. I just watched [S] Cryscalmetheborn: Enter and that was a pretty cool dub over.

The Condesce made Jane heiress because she was a Crocker and she was going to inherit the Betty Crocker baking empire when she became of age. 

She was exploring space and conquering new races and planets. 

You can see the Helmsman on this page.  

Not every gold blood has psionics and the bulge thing (if canon) would only be the captors due to their duality theme

Yes, the Alpha kids experienced everything relatively the same up until they entered, then there were some small differences.