Crack of Time (aka Chasm of Time) is a dimension that exists separated from time and all 12 universes yet at the same time interconnected with each universe. It is a location that appears in the Dragon Ball Xenoverse series and Super Dragon Ball Heroes: World Mission.
In 75 Million Before Age, Chronoa and Mechikabura fight for the position of Supreme Kai of Time. After realising Mechikabura's evil intentions, Chronoa became the Supreme Kai of Time and sealed Mechikabura away in the Crack of Time. Chronoa punished the Demon God Demigra for his attempted takeover of the Time Nest, by sealing him in the Crack of Time which became Demigra's prison. During the 75 million years he was imprisoned, Demigra trained to increase his power and magic abilities.
75 million years following his imprisonment the various time distortions caused by the Time Breakers Towa and Mira weakened the barrier separating the dimensions, allowing Demigra to send mirages of himself to further his plans to free himself by creating more time distortions; that would be enough to create a portal to free himself and upon his escape he planned to use his new-found power to seize control of time and the universe.
Eventually he managed to escape and consume Tokitoki gaining greater power as result. After facing opposition from Goku, the Future Warrior, Future Trunks, and the Supreme Kai of Time, Demigra decided to simply destroy the Time Nest, which would erase all of history and the universe in the process while he himself would watch from the safety of his former prison in the Crack of Time due to it existing outside of time. After history was erased Demigra planned to remake the universe into one he controlled. However the Future Warrior managed to follow him through the portal Demigra used to escape the destruction of the Universe and into the Crack of Time where they face off against a transformed Demigra. Goku also managed to enter the Crack of Time using Instant Transmission, which shocked Demigra who was unaware that the Crack of Time could be easily breached via Instant Transmission.
In the normal ending, SSJ3 Goku and the Future Warrior counter Demigra's desperate final attack with a Friend Kamehameha that is powerful enough to destroy both Demigra and still have enough power to damage the Crack of Time causing it to collapse.
In the alternate ending, the Warrior manage to defeat Demigra before Goku arrives by Instant Transmission, causing the Warrior to counter Demigra's desperate final attack with a solo Kamehameha, only to be momentarily overpowered by Demigra's attack during the Energy Clash, but is saved by the spiritual assistance of Goku, Vegeta, Gohan, Piccolo, and Krillin who each lead the Warrior their energy and word of encouragement, resulting in the creation of the Z-Spirit Kamehameha technique that proves powerful enough to destroy both Demigra and still have enough power to damage the Crack of Time causing it to collapse.
In both endings following Demigra's defeat, the Crack of Time starts collapsing, though the Future Warrior, and Tokitoki escape safely by using Goku's Instant Transmission or by Tokitoki teleporting the Future Warrior out if Goku didn't arrive to the fight.
However in the Unknown History Saga of Dragon Ball Xenoverse 2 it is revealed the Crack of Time survived and still exists separate from history which is taken advantage of by Dabura during his revenge on the Time Patrol for its role in his sister's death in Age ???. It is revealed that Towa had secretly prevented Dabura death in Age 774 during her infiltration of the Time Vault in Age 852. Dabura manages to take Chronoa prisoner and brings her to the Crack of Time imprisoning her in the same place she had imprisoned Demigra millions of years earlier. Fortunately she is saved by the intervention of the 2nd Future Warrior who along with their chosen partner defeats both Dabura and Demigra whom Dabura had recruited from an alternate timeline.
The Crack of Time is a lifeless void containing crystalline structures called "Time Chasm Crystals", which allow someone to view events of both the past and present. Due to it existing outside of time, anyone residing in the Crack of Time would be immune from being erased from history if the Time Storage Vault was ever destroyed, which Demigra used to his advantage when he attempt to destroy the Time Vault as part of his plan to remake the history of the universe as he saw fit,—somewhat ironic considering the Crack of Time was meant to be his prison, yet almost ended up allowing his plan to rule all of Time and Space to succeed.
The Supreme Kai of Time states that it is joined with many eras and technically shouldn't even exist. As a result, nothing that occurs in the Crack of Time can be considered strange nor impossible, such as when the Future Warrior saw visions of Goku, Vegeta, Gohan, Piccolo, and Krillin in the Crack of Time, which resulted in the Z-Spirit Kamehameha that defeated Démigra in the alternate ending.
- Mechikabura - Sealed here by Chronoa prior to Demigra being imprisoned.
- Demigra - Originally imprisoned here in 75 Million Before Age. 75 Millions years later having lived here since he was sealed, Demigra finally managed to escape yet used the Crack of Time as a base and as a safe haven during his plan to remake the universe by destroying the Time Vault.
- Dabura - After being rescued from death in Age 774 by Towa after she secretly used the Time Scroll during her infiltration of the Time Vault in Age 852, Dabura used the Crack of Time as a base during the Infinite History Saga when he sought to take revenge on the Time Patrol for its role in his sister's death in Age ???.
- Future Warrior - Visited the Crack of Time when they chased after Demigra through a wormhole.
- Goku - Visited the Crack of Time while following Demigra's ki using Instant Transmission and managed to teleport into the Crack of Time, a feat Demigra didn't believe was possible. Goku also visits during the Infinite History Saga when working as the 2nd Future Warrior's partner.
- Tokitoki - Brought here by Demigra as a result of being captured and consumed alive by the Demon God. After being freed from Demigra, he escaped from here along with the Future Warrior (and Goku in the normal ending).
- Chronoa - After being captured by Dabura in the Infinite History Saga, Chronoa was ironically kept prisoner here until she was rescued by the 2nd Future Warrior and their partner.
- Future Warrior - Confronts Dabura and Alternate Demigra here during the Infinite History Saga.
- Sealas - Can be seen here shortly before he uses a Wormhole and invades the Time Nest in World Mission.
- Interestingly, the World of Mind Control in Dragon Ball Xenoverse 2 resembles the Crack of Time. Presumably the level design of the Crack of Time from Xenoverse was retooled to create the World of Mind Control that appears when the Future Warrior falls under the effects of a Brainwash Attack.
- Additionally the Time Rift stage from Xenoverse 2 has an identical appearance to the Crack of Time (it even features the same background music track). In the main story, Towa attempts to trap the Future Trunks and the Future Warrior inside the rift, similar to how the Supreme Kai of Time sealed Demigra after his defeat in 75 Million Before Age. However Towa fails as Bardock uses a ki blast to knock them away and angry over being manipulated puts Mira in a Full-Nelson and pulls him into the rift, trapping them both. Bardock then battles Mira inside the rift, transforming into his Super Saiyan, Super Saiyan 2, and Super Saiyan 3 forms as the fight progresses. After Bardock defeats Mira in the main story, the Time Rift is unlocked as a selectable stage. However, it is unclear if they are the same location with different name, separate dimensions that are identical due to them both being dimensions outside of time (its also possible that the developers simply recycling the Crack of Time's level design from Xenoverse to create the Time Rift stage in Xenoverse 2).