"You're still playing with that?"
"For the last time, I am not playing with it."
"It looks like you are."
"Seriously, how old are you supposed to be?"
"Same as you, I'm just more fun — even our mother variant is more fun than you."
Back in the Council of Ross, the dead universe was still dead, but the activity going on inside it could not be even more alive, even compared to when the Council of Ross was still actually the Council of Ross and not just a hub for multiversal friends. Or in this case, Dr. Caitlain and Dee, Diana's variants.
Dee was previously in another dead universe, but opted to bring her work into the Council of Ross instead since she could use another eye to help her. Unfortunately for her, the only other one crazy enough to actually help her in experimenting with the Cosmic Compressor was Dr. Caitlain… and Dr. Caitlain never stops talking.