(From MS Paint Adventures: Homestuck. Click for full-sized black hole accretion.)
As it turned out, not even the entry of Jake, Roxy, or Dirk into the medium was going to be saved for the end-of-sub-act flash (nor was it necessary for Roxy or Dirk to return to the future and actually be present for their own entry into the medium, which Dirk’s robots Sawtooth and Squarewave chaperoned instead), with those events instead being handled in a series of updates released shortly after Hussie’s trip to Comic-Con.
What was big enough for the end-of-act flash? The full reveal of Calliope’s brother, taking a back seat (to the point that his name, Caliborn, is almost casually dropped in the command) to his escape and entry into the medium. He apparently stays in the sarswapagus long enough that his red spiral fills up to become a red disc (though the exact cause isn’t clear), then gets up, unlocks his own shackle, and proceeds to gnaw his own leg off to be rid of the other shackle, casting a rather Lord English-esque silhouette in the process. As much as it’s been hinted before, that all but admits that Caliborn is, in fact, a young Lord English by explaining much about his appearance, even the tooth he spits out afterwards. We then see that his cruxtruder is showing “~U” rather than an actual time, and his kernelsprite apparently turns into a black hole that sucks up his house, the Statues of Liberty, even the planet itself; it might be the same black hole that appears at the end of the flash (in the image above), leaching away material from the red supergiant the cherubs’ planet was orbiting.
What’s that? As much as you understand it, you don’t think that outweighs the deaths of the protagonists or their entry into the medium as candidates for the end-of-act flash? Oh, I forgot the part with Lord English himself, where he utterly destroys a dream bubble and everything in it. Or the part where Jack Noir and the Peregrine Mendicant apparently stop fighting upon reaching the scene of the crime… including, apparently, some maimed horrorterrors. (If the black hole at the end of the flash is the one Caliborn left behind, what, exactly, are they reacting to? The remnant of the explosion, the maimed horrorterrors, something else?) In the end, this flash might be the most dramatic flash we’ve had so far that didn’t end Acts 4 or 5.
But more than that, I feel more than ever like we’re actually getting back to the actual plot. This flash focuses away from all the new characters and squarely on Lord English (even Caliborn ultimately serves the purpose of illuminating the similarities between him and English); it fully establishes the threat that Lord English presents and sets him up as the main villain of the rest of the comic, utterly overshadowing the Condesce, Jack Noir, the horrorterrors, and everything else. With Hussie promising a third intermission after this next break, the focus is about to move back to the main, established cast and their race to stop Lord English and put a stop to his threat for good – possibly with help from the comic’s other villains. If Lord English is the force that’s killing them, I actually suspect it’s doubtful that the horrorterrors were working in cahoots with Doc Scratch after all, but accidentially misled Rose into creating the Green Sun, perhaps because Doc Scratch perverted their intent or orders. The other case is if the Green Sun plays a key role in English’s defeat, whether because of the presence of PM, Jade, or even Jack Noir, or for some other reason; contrast the Green Sun with the red giant the cherubs’ planet orbited and that we see at the end of the flash.
On the other hand, given this circumstance I’m not sure I like the notion of Caliborn being a young Lord English. Even though he is an unredeemable asshole, it seems like it might humanize him too much, given his status as an utterly implacable villain above all villains, who even the comic’s resident Lovecraftian abominations fear.