I started rereading Homestuck and I'm at the first Intermission. And there is this scene where Die pushes Spade Slick's pin into his doll. This allows Die to jump to the moment when Spades died. But instead, he jumps to Alternia(?) and it says "How many times does he have to tell you. He made this town." I'm confused. How does Die appearing in Alternia(?) prove that Spades made the town?
Spade Slick founded Midnight City on post-Sgrub Alternia. When Die teleported to a timeline where Slick died and the city wasn’t there it proved that Slick did in fact “make the town”. Slick is alive, the town exists. Slick is dead, the town doesn’t exist. Therefore for the city to exist, Spades Slick had to be alive to make it.