Earth-7484 (Classic Deathlok Future Timeline)
Henry Akai was a scientist who worked for Roxxon as part of the Nth Command. He was instrumental in creating the Nth Projector, a device which could bridge the gaps between different dimensions and timelines. He was also good friends with an Nth Command field agent named Godwulf.
In this timeline the Nth command was successful in carrying out Operation: Purge, using the Nth Projector to banish the Avengers the X-Men and the Fantastic Four, along with various other heroes and villains into hostile dimensions antithetical to life. However the overuse of the Nth Projector overloaded it, and the machine exploded. The device's chronal energy mutated Akai, giving him the power to travel between time and space.
With the world's defenders removed, corporate and military entities began to stake their claims on the world. Harlan Ryker began a brutal war a]to conquer America using cyborgs like Deathlok.
For his part, Akai, now the superhuman known as Timestream, used his powers to conquer Japan. He also supported and sponsored Godwulf's overthrow of Ryker in exchange for part of America. When Godwulf refused to hold up his end of the bargain, Timestream attacked America, killing Godwulf's Redeemers but failing to defeat Godwulf and Luther Manning.
Godwulf allied himself with the Time Variance Authority, who were displeased with Timestream's powers, and Timestream was captured. Godwulf couldn't bring himself to kill his own friend and instead imprisoned him. Timestream, however, easily escaped and fled the timeline.
Timestream later summoned Michael Collins, an iteration of Deathlok from the Earth-616 timeline into a parallel future, wrongly believing him to be another incarnation of Luther Manning. Timestream at first posed as a freedom fighter, seeking to wrest control from a machine dictatorship. He pulled an army of elite warriors from different places and attacked the mainframe. Collins would soon discover, however, that he simply wanted to control the mainframe and replace the current rulers. Collins stopped his plans, and Timestream transported himself away, vowing vengeance.
Timestream realized that he had selected the wrong Deathlok, that Luther Manning, the man he wanted, had been prevented from becoming Deathlok by a shift in the timeline. Timestream infused Luther with chronal energy, seeking to turn him into a weapon. This transformed Luther into another Deathlok, who Timestream took control of with a virus. Timestream also summoned more cyborg warriors from various times, including the much older Luther Manning from his own timeline, now called the Demolisher. Timestream planned to destroy both the 7484 and 616 timelines by altering the flow of time, creating a new timeline where he ruled supreme. In exchange he promised to turn both versions of Luther Manning back to their human forms. In response, the TVA dispatched Godwulf, Michael Collins, and Siege to maintain the current timeline.
Timestream and his soldiers arrived in the past of Earth 616. They at first tried to prevent the merger of the past 7484 Luther Manning with his clone, leaving Deathlok under the control of the Brand Corporation. This plan was foiled by Godwulf, Siege and Collins. They next tried to send the transformed 616 Manning into the future in the place of the past 7484 Manning, preventing Godwulf from overthrowing Ryker in the future. This plan too failed.
In order to escape Timestream cast his enemies into the liminal space between timelines while he formed a new plan. His enslaved 616 Manning was soon destroyed trying to free itself from Timestream, but Timestream and the Demolisher managed to flee into the past of Earth 7484, on the day of Operation: Purge. Timestream now intended to kill his past self before he could become timestream, creating a paradox and changing his future entirely. What exactly he thought would be the outcome is unknown.
The Demolisher soon realized he was being manipulated and turned against Timestream. Shortly afterward Godwulf, Collins and Siege would follow Timestream to the day of Operation: Purge with the help of the TVA. The Demolisher would join them and the heroes fought against Timestream to protect the younger Henry Akai and preserve the timeline. Timestream seemed to be winning until Collins blasted him with Akai's Nth Projector. The Projector's energy cancelled out Timestream's own, and Timestream seemed to vanish, though his fate is unknown. TVA agent Justice Peace then returned the heroes to their own timelines, and wiped the younger Henry Akai's memories, so that he would still be in proximity to the Projector when it overloaded, maintaining the flow of the timeline.
Earth-616 (Prime Marvel Timeline)
Henry Akai was a scientist who worked for Roxxon as part of the Nth Command. He was instrumental in creating the Nth Projector, a device which could bridge the gaps between different dimensions and timelines.
In this reality Captain America was warned of Operation Purge by the Godwulf of Earth-7484. Captain America was able to destroy the Nth Projector's power source before it was used, preventing Operation: Purge entirely. Consequently the Nth Projector did not overload and presumably Henry Akai remained an ordinary, if brilliant, human.
Powers and Abilities
Henry Akai was a gifted physicist, with knowledge of multiverse theory. He was instrumental in creating a device that allowed for dimensional travel.
After being exposed to space-time energy by the overload of the Nth Projector, the Henry Akai of the Earth-7484 timeline became the being known as Timestream. Timestream ha the power to transport himself, proximate objects, and people through time, either from various points in one timeline or by hopping into another. He was able to warp reality by manipulating probability (For example he was able to take a Luther Manning who was not Deathlok and transform him into Deathlok, wither by drawing upon similar realities or by accelerating time) He was able to accelerate or reverse the aging of objects. He was also able to access the liminal space between times, which he uncreatively also called the "Timestream."
Timestream made use of a "Timesword" a blade of unknown material and properties, which seemed to conduct his energies and powers.
Timestream also made use of the Timeskipper, a more conventional time machine that allowed him and his entire army to travel without expending Timestream's energies.