Let a lore master handle this.
Bump old threads that people recognize as Symbols of Chaos. Fatposter's, -AkiraKurusu-'s, etc. Then after bumping three, if your heart is filled with undying love for chaos, then the Old Gods will awaken to destroy the site and our world. It's unknown if Old Gods are users of the forum or some unknown entity, but my theory is that Mishima made this site to keep them contained.