Null session

A null session in Sburb is any session of the game that is doomed to failure.

While this refers to any session that fails to create a universe, it also seems to refer to sessions where the players create a universe but are still unable to win. Both Karkat Vantas and Aradia Megido call their own session a null session after Jack Noir prevented them from obtaining the Ultimate Reward, even though they successfully created a universe and killed the Black King.

According to Rose Lalonde, null sessions are actually very common; she notes that redundancy is a property to be expected in any reproductive system, and universes are no exception. As Skaia is "aware" of its own fate, null sessions are doomed to fail by design; the scratch can offer a second chance of sorts by resetting the universe, though the new session that results may also be null.

The session glitch is hinted to create a null session.

Void session

The Prospit or Derse of a Void Session

A void session is a specific type of null session where none of the sprites are prototyped pre-entry. On the one hand, this prevents the underlings and monarchs from gathering any significant powers from prototypings. On the other hand, such a session cannot be won as the Battlefield will not reach its final form, preventing the creation of a new universe. The players will be doomed to live out the rest of their lives in the session unsuccessfully, shy of an incredible act of intervention beyond their powers to influence.

There are a few traits unique to void sessions that are encountered by the post-scratch kids. In a void session, both Prospit and Derse lack prototyping towers, as Skaia is already aware there will be no pre-entry prototypings. Also, lacking any pre-entry prototypings, the Underlings encountered in void sessions are skeletal, which are highly difficult to kill and produce almost no grist. Lastly, the Reckoning does not occur in such a session, as the White King never falls in battle due to the everlasting Stalemate that occurs if nothing is Prototyped.

The players of such a session can be referred to as Nobles instead of Heroes, because under normal circumstances such a session is slated to end in failure and the players cannot fulfill their heroic destiny. This is also a chemical reference, as the noble gases cannot react naturally, just as this session cannot be completed naturally.

All the consorts of each planet in the post-scratch kids' session had died out by the time they arrive (though their denizens still live), and we read that "The Aspect of Hope was dead on arrival"; however, it is unclear if this is a common trait of a void session or an anomaly specific to their session.

Each planet in the only known Void Session have a different naming schema than those of a Null Session, such that they are the Land of [Grave] and [Noble Gas]. This may be a reference to the fact that there are no living beings on the planet as all the consorts are long dead and the only creatures other than the players are mobile skeletons, and to the fact that the instead of being referenced as Heroes the player characters are referred to as Nobles.

Dead session

A dead session is a subtype of void session where there is only one player. Because Sburb requires a diversity of powers and interaction between characters to function properly that only a multitude of players can provide, there is no means of creating a universe in such a session under any and all circumstances, even with outside help. Dead sessions have been described as “almost unrecogniza8le” compared to other sessions, with victory and defeat being dictated by totally different terms. It is considered to be the extreme difficulty of Sburb and is designed to be impossible to win; a dead session exists almost exclusively for the purpose of punishing its player for attempting to play the game alone.

The carapacians wear different clothes from other games. There is no ectobiology, with the player being born biologically rather than by paradox clones, and no exiles. There may be no denizens too, as Caliborn's Yaldabaoth was brought from Dirk's planet; since Alternate Calliope also had a denizen, its likely the game "steals" them from other sessions to have a goal.

Skaia before a dead session begins.

Prior to the session being launched, Skaia is permanently covered by dark clouds. Only the Cruxtruder is able to be deployed, and the kernelsprite it releases collapses into a black hole. This black hole serves as the entry mechanism, sucking up the player's home planet and sending it into the Medium. The planet then acts as the player's land, though it lacks most essential features like consorts, underlings, gates, or even a Land of X and Y name.

Before the player can gain an audience with their denizen at the planet's core, they must first find the key to its lair. The denizen will offer the player a particularly potent and dangerous variation of the The Choice, which serves to describe the two different paths the session can take from this point onward.

After the player accepts their denizen's Choice, the game starts and Skaia turns into a solid black sphere, whereupon it explodes in an event known as the First Break. From this blast, fifteen new planets emerge and scatter across the Medium before falling into orbit around the former location of Skaia, now occupied by a black hole. Some of these planets may lose their footing in the orbit and spiral into the black hole, an event considered rare and fortuitous.

The player's goal is to take over and destroy each planet in order (with the exception of the eighth planet, which must be destroyed last or else the session is lost). On each world, the player must crush all form of resistance, the last and most dangerous of which being a powerful underling who rules the planet, before venturing into the planet's core to retrieve a powerful "cue ball" bomb. The bomb isn't strong enough to destroy a planet by itself; rather, the explosive must be carefully placed on the surface of the planet, such that the force of its detonation pushes the subjugated world into the black hole, or "sinks" it. Each planet is more difficult to defeat than the one before it, and there is a time limit on each planet, which gets shorter as the player conquers each one: if a player fails to destroy a planet in time, the bomb detonates prematurely out of position and the session is lost.

According to Alternate Calliope, the challenge is rigged in favor of the Aspect of Time.

To assist the player, every time they conquer a planet a leprechaun minion is generated and becomes their servant, each bearing a unique magical power. If they choose to fight their Denizen later, they will get great rewards.

Examples

Every session seen or heard about in Homestuck is some kind of null session, with the exception of the session fedorafreak was in.

Although the precise circumstances of their session are unknown, the players of pre-Scratch Alternia were in a null session due to the session glitch and the presence of a Tumor.

The troll players of post-scratch Alternia, as previously stated, were successful in creating a universe. However, it seems their session became null after Jack Noir prevented them from entering the newly created universe, an act stemming entirely from their failure to breed a stable, cancerless genesis frog. It is implied that Doc Scratch and Lord English had deliberately engineered this result through their subtle machinations and corruption of troll society.

The pre-scratch kids also had a null session. This is the more direct result of the cancer Karkat gave their universe by failing to breed the Genesis Frog correctly. The manifestation of this was the massive overempowerment of Jack Noir, who ruined the session by killing and usurping the Black Queen and Black King and initiating the Reckoning prematurely, as well as in the form of the Tumor growing within the battefield, which went on to produce the Green Sun.

The post-scratch human session is intrinsically a void session. Jane Crocker did not prototype anything before entering her session (due to interference from God Cat), and neither did the other players (due to more pressing matters, such as escaping the Miles). Even if their session was not circumstantially void, it is evident it would have been null regardless due to the fact that they had no Space player to breed the Genesis Frog (nor a planet where the frogs would be found or even a Forge) and create their new universe. However, this does not mean the session is hopeless. The very fate of the session was to become one of eight players, with Jade (a Space player) bearing a fully prototyped Battlefield to occupy the void session's functional Skaia, as well the Genesis Tadpole she made. Dave's presence in the session also provides the necessary Time player.

The cherubs' session played by Caliborn is a dead session, as Prospit is shown not to have any prototyping towers much like the Prospit and Derse of the post-scratch human session. Storm clouds had grew around and eventually completely surrounded Skaia before entry. He earns the denizen's key by completing a series of tedious chores. It wasn't until he began the conquest of his session's planets that he gained access to alchemization, demonstrated by his wearing a customized Caltop helmet. The leprechaun minions granted to Caliborn are the past versions of the Felt; before his conquest began, the seventh, eleventh, and fourteenth planets spiraled into the black hole without Caliborn's interference, matching the three Felt members killed by the Midnight Crew prior to their invasion of the Felt's manor.

An Alternate Calliope also played a dead session, but chose to be killed by her denizen and fullfill another goal in the dream bubbles.

Trivia

• In the C-derived programming languages, the words null and void are used. A variable with a null value has no data assigned, while a void function is one that does not return any data.
• The goal of a dead session draws clear reference to billiards, a game in which a player must use the cue ball to sink all balls of one type (solid or striped) and then sink the eight ball; sinking the eight ball before all balls of the player's type is an automatic loss.