Karkat's anger/Sollux fails to embrace his role
Sollux: Deal with apocalypseArisen.
Aradia was talking about how Sollux seems "sad and angry all the time," and she mentions that she doesn't remember what anger feels like. Sollux retorts that she should ask Karkat, since he's so mad all the time. Aradia responds as follows:
AA: i think his anger serves a greater purp0se
AA: its part of his destiny and thus 0urs
AA: it will help him t0 sab0tage his 0wn designs
AA: which are very much in 0pp0siti0n t0 the br0ader purp0se
AA: and will s0w the seeds 0f 0ur failure
AA: a failure which will ir0nically pr0ve t0 be missi0n critical
That conversation got really deep really quickly! I had to take note of this because it's clearly tapping into Intense Plot Shit, stuff that the reader would have no idea about yet on a first read-through. What it brought to light for me this time around is that, basically, the trolls not only were destined to fail, but really were supposed to. Not because of Doc Scratch's machinations, but in spite of them. Their session was sacrificed, quite frankly, because paradox space had bigger fish to fry. A chain of events had to occur so that three sessions could collude to go up against a bigger nemesis than the Black King and Queen: Lord English.
I'm going to change tracks now, but first I'm going to quote more from the pesterlog. This is a little later in the conversation, after Aradia reveals that Sgrub will not, in fact, save the world, which is what Sollux had been led to believe:
TA: ii dont want two play anymore then.
AA: y0u will th0ugh
TA: fuck that ju2t watch, thii2 2hiit iis du2ted.
TA: check me out, all du2tiing iit liike a 2aucy fuckiin maiid.
AA: it cann0t be st0pped
AA: mete0rs are en r0ute
AA: y0u kn0w this s0llux
TA: who care2, iim yankiing the grubtube on thii2 overpunctured biitch.
TA: iim telliing red team leader two forget the whole thiing.
TA: iim quiittiing a2 blue team leader.
TA: iif you want two 2hamble through thii2 macabre fanta2y of your2 2olo be my gue2t.
So basically he finds out the game isn't going to save Alternia and he's like, "fuck this I'm out" despite all he knows and all he's seen visions of. This is a direct rejection of his role as the Mage of Doom: Sollux's classpect is all about knowing the inevitable, accepting it, and doing what needs to be done (which often requires sacrifice). It's possible that this attitude is what earns Sollux his first death (which I haven't gotten up to yet but I will link to when I do)--as per bladekindeyewear's Ultimate Riddle theory, that kind of attitude would mean Sollux loses some of his reality-influencing privileges.