Have you heard of the theory called the Mituna Method? We know that Mituna burnt himself out doing something with his psionic powers, which aranea described as "some great act of heroism". The theory proposes that he launched A1's Prospit (or its moon) out of their session and on a path to eventually end up in the B2 session, where the surviving trolls could use the sacrificial slabs to ascend. That seems like it has the right amount of buildup, since Tuna's overexertion is yet unexplained.
I’ve heard of it but I don’t think it’ll become canon. That seems like a pretty big plot point for a character that Hussie never originally intended to introduce.