The Yellow Yard
The Yellow Yard is the limit of Andrew Hussie's direct interference in the story of Homestuck. This limit was first established in a fourth wall-breaking message to the reader
, in which he explains that his frequent self-inserts will inevitably cause him to directly interact with the story he created. To prevent this from ruining Homestuck, he chooses to restrict his interference to a single, passive moment located entirely within an area the size of the distance light travels in three nanoseconds: one yard.
In Seer: Descend there is a book which reads:
"Though we adore Him we shall never enjoy His beauteous Croak. We spill our blood on acres of black and white so they may cross the yellow yard. At last in Skaia's reflection through broken glass He may find the pond in which He's meant to squat."
According to Karkat, Jade's plan involves a yellow yard (which he calls a "lawn ring", the troll word for a different kind of yard). In [S] Cascade, it is revealed that Jade's plan is to use the Fenestrated Wall that she captchalogued on her future self's instructions (passed on via Karkat), expanding it until it is large enough to fly through on a Prospitian ship, taking John, the Battlefield and the kids' planets with her. In Intermission 2, the ship is seen emerging from the Fenestrated Wall on the right in Hussie's apartment, just after Lord English retrieves his coat, and starts to cross the Yellow Yard.
Although the trip would only last three nanoseconds from Hussiebot's perspective, it would take three years from John and Jade's perspective.
It is not yet known what lies beyond the opposite Fenestrated Wall, however it will most likely be the Sburb Session of Jane Crocker, Jake English, Roxy Lalonde, and Dirk Strider. It is implied that Jake's Grandma stole the fourth Fenestrated Wall from Derse, much like Jane's Grandpa may have his, sometime before The Imperial Condesce usurped the Black Queen's throne. There's a possibility that this Fenestrated Wall is the object taking up a majority of the space in Jake's Captchalogue Deck.
The Yellow Yard and the second Fenestrated Wall, as seen by John and Jade.