The Reckoning rains meteors on Skaia.
The Reckoning is a twenty-four hour event in Sburb within Homestuck that occurs when the forces of dark achieve their inevitable victory over the forces of light on the Battlefield in the center of Skaia. Triggered by the combination of the Kings' scepters, a rain of meteors hurtles toward the Battlefield from The Veil, and Skaia defends itself using portals to transport the meteors toward the session's host planet instead, throughout its timeline. Most of them arrive around the same time during the initiation of the session, providing the initial motivation to enter the Medium in the first place.
In a normal session, the Black King or Black Queen eventually captures the White King's scepter and uses it to initiate the Reckoning. After this point, the meteors are sent towards Skaia, starting with the smallest and gradually sending larger ones. The Heroes have twenty-four hours to defeat the Black King and Queen and end the Reckoning before the largest meteors destroy the Battlefield and render their session unwinnable, as in the pre-scratch trolls' null session.
The post-scratch trolls managed to avoid fighting the Black Queen by exiling her before the Reckoning, with the help of Jack Noir. The pre-scratch kids' session of Sburb, however, had its own version of Jack Noir start the Reckoning much earlier than it is supposed to occur in an average session.
After killing the Black King on the Battlefield and thoroughly wrecking the white and black armies, not to mention the planet, Jack Noir receives the White King's Scepter from the Courtyard Droll. Jack then uses it to begin the Reckoning early, sending the Veil's meteors towards the ravaged Battlefield.
In a void session, such as that of the post-scratch kids, the Reckoning does not occur, because the failure to prototype any kernelsprites before entry causes the Battlefield to remain forever in its initial stalemated state.
Paradox clones[]
A countdown to the Reckoning.
The Reckoning is an important part of the story of the paradox clones. At some point after being "born", each paradox clone is transported onto one of the meteors in the veil, and with it, through Skaia's defense gates, to the player's home planet, into the past, thus creating them in the first place.
Each of the clones from the kid's universe took with them an object or animal: Grandpa takes his revolvers, Nanna takes Dad's oil-stained fedora, Mom takes Mutie, Bro takes Dream Lil Cal, John takes the Colonel Sassacre book, Rose takes the original bunny, Dave takes Maplehoof, and Jade takes the Knitted Bunny.