Primeval Era of Taros
After the Sorroda Contact, life had indeed begun appearing within the Taros Cluster thanks to the efforts of the Deities contracted to bring it to life.
Tarosian Pylons
Some of the earliest notable structures to appear within the Taros Cluster were crystalline structures known as 'Tarosian Pylons' capable of generating an unusual wormhole-like effect with the lifeforce of proximate beings, allowing individuals to use them to translocate to other active Pylons. Despite the hypothetical chance of them being made anywhere, the Taros Cluster's fairly anomalous lifeforms gave them enough power to readily be formed in the cluster, appearing in ever-increasing volumes thanks to the mutual bond and lifeforce of the natives of the cluster. If a sufficient amount of sapient beings inhabited an area near to one of the Pylons, the wormhole effect activated, allowing anyone who wished to use them as a instant transport method to other active Pylons. These required a unique environment, as each planet could only have a couple active pylons, the exception tot his of course is supremely powerful beings whom hold enough knowledge and power to already fully control their destinations.
The High Priest needed a way to swiftly transport the Celestial Army, as they were not capable of his vast travels unlike himself. He dispatched his clone to retrieve the crystals forming the Tarosian Pylons, even if they became inert outside of the cluster. Initially they did not work, until he began experimenting by having the crystals be located in distinctly Tarosian terrain. This did surprisingly work, Four pylons made out of each species of the Celestial Army's homeworlds were constructed, each allowing the armies to instantly warp into battlefields. The crystals within these pylons were warped, as the High Priest used mass death to feed the crystals' power. These pylons are protected with shielding, making it very difficult to breach through. Using this new technology, all remaining worlds within the High Priest's territory were fully subjugated, after which the High Priest created the 'Advanced Information Analysis Unit' to surveil the Taros Cluster's development. The usage of the crystals greatly offended the Protoss for some reason.
Creation The Dark Heart
Contrary to popular belief, not every Elder God was needlessly malevolent or evil as some of them had strong moral compasses and opposed their brethren's constant manipulation of lesser organic beings with the most notable among the benevolent group being the Abyssal Lord, a being with a remarkably elderly form. He had spent his life battling the other Elder Gods and trying to thwarting their plans, thus it was only natural that when he came across the Advanced Information Analysis Unit, and saw the High Priest within it, alongside his grand plan he managed to figure out that the High Priest aimed to use the Taros Cluster as a incubator for his one true army, giving him the power to raise destruction across the cosmos. Stopping such a plan would be hard, and maybe even lethal so he would have to be careful. He snuck into the heart of The Core sustaining the artificially accelerated evolution of life in the star-cluster and lit a all consuming flame known as The Dark Heart, whose job was to suck out all of the life within the Taros Cluster so that the High Priest's plans would not come into fruition. The Dark Heart was made to act slowly, so that the High Priest would not notice.
He could not be sure what would happen if the plan would go wrong, so he decided to stay in the Taros Cluster and pretend to be a local Tarosian so that if anything went wrong with the Dark Heart he may repair it. Only a little time after the Dark Heart was placed, irregularities had already been noticed. The core was dropping rapidly in temperature, forcing the Builders to constantly regulate it. They claimed it was because of the planet's artificial creation, trying to keep the truth hidden from the High Priest and the Deities so they may take the power of the Dark Heart for themselves one day. Regardless of this, the Abyssal Lord decided to remain just in case so he may prevent the rise of The Fifth Race, ignoring all external telepathic messages (such as ones from Miraak) to avoid detection.
Builders of Hellae
The Core did not ignite as was planned, the planetoid created for the specific purpose of maintaining the accelerated life within the Cluster thanks to the existence of The Dark Heart unbeknownst to the High Priest and Deities, thus a work around was devised to prevent all of their work from falling apart; The Builders were offered a chance to remain in The Core to keep it lit, but they refused as they did not want to be eternally trapped in the heart of a planet. The Deities had little choice though, so they trapped the Builders within the heart of the Core so that they may work as they were told that they shall either maintain the planet, or die alongside with it. The Builders, who had ran out of option decided to stay and work as they now had no other choice, leaving them trapped within the Core for the rest of time, slowly forgetting who they were and turning feral. They still worked though, as it was all they could do.
Beginning of life
The Taros Cluster still needed life, and letting it form on its own would take too long for the High Priest, so the Deities initiated the process at a much more accelerated rate by raining down some of their own blood onto the Taros Cluster so life may emerge, leading to their blood bubbling into the first generation of Limoans. The Limoans quite literally were the primordial ooze of the taros cluster, once resembling mere inanimate sludge but slowly coming to life, changing and adapting to their surroundings by spreading across the entire cluster, changing to look more like the areas they resided in. While many Limoans remained as they were, absorbing smaller organic matter or feeding off of moisture, many of them did in fact evolve to fit all kinds of niches within the Taros Cluster. Their descendants even sometimes managed to become christened as protectors of the Taros Cluster.
The Heartkeepers
As the Builders of Hellae worked tirelessly within The Core to keep the Taros Cluster living, they were disappointed by the lack of gratefulness to their torment. They were only seen as demons, but over time their bodies did start changing to fit that description to better suit their work within The Core. A group of the Builders decided something HAD to be done, beginning research into the nature of the heart of The Core, trying to figure out why it had not ignited leading to their entrapment until they finally discovered the Dark Heart embedded in the centre of the planet, which was sapping away at the energy of The Core. It was too late to undo this by now, so they had to find a way to deactivate it rather than destroy it, leading to the "Heartkeepers" trying and failing to reverse-engineer how it was created and how to destroy it
The Dark Heart was clearly made by someone way wiser than themselves, as they simply could not comprehend how it worked and the longer the experiments occurred the Heartkeepers began becoming more strange and erratic even if said traits were ignored ignored as the effort was considered vastly important. This inaction did however change, as one day a group of researchers vanished alongside a sample of the Dark Heart, with search parties eventually finding the group praying to it in a secluded location. It was obvious the Dark Heart had started to have a sway over the Builders, thus the higher ups in charge of this operation had no other choice but to abandon the project, and exile everyone involved.
Exile
The now exiled Heartkeepers were forced to leave The Core, settling on a habitable moon orbiting Taros-Prime known as Thess where they continued to work on a cure for The Dark Heart for a long time, slowly changing to fit more like natural creatures of the planet while the other builders on The Core slowly started becoming primal and only focused on working to keep The Core active. The Heartkeepers eventually did however decide to lock away the Dark Heart, returning to a more simplistic way of life even if the Dark Heart would not simply be truly locked away, for during the initial experimentations the Dark Heart was used to enchant several weapons and tools which had over time made their way to the inhabited planets of the Taros Cluster, where its eventual fate remained unknown.
