The room trembled and shook. Explosions erupted and consumed all sound. The entire place was falling apart all the while a battle took place. The large chamber dimly lit with pulsing purple light was on the verge of collapse, just like the rest of the building. Emitting the glow was a giant runic spell circle, pulsing faster and brighter every moment that passed. What started as a dull throb at the start of the battle, was now a steady rhythmic pulse, and the heroes watched in dismay as they continued to fail at besting the evil in front of them. The spell was a taunting reminder that this was their last chance, and time was running out. When they began they were well-coordinated and worked as a team but now most lay crumpled and unmoving. Blood mixed with the dust of the crumbling structure and crunched under the boots of the lead hero as they once more charged forward. Their armor was broken and useless, while their weapon had lost all magic protection so as to be nothing more than a metal club at this point. The evil breathed heavy but stood tall knowing they would be the victor of this fight. They had far more in reserve than the others. Throwing another blast of similarly colored purple magic at the charging figure they roared with laughter, the magic pulsing brighter and faster behind them. Unbeknownst to everyone at some point in the battle the magic circle had been damaged. It was unclear which side launched the attack that did it, or how long ago it happened. All that mattered now was that it was too late to stop. With a final burst of blinding purple energy, the spell circle erupted launching and decimating everything. The evil and the heroes all perished. The room and building finished collapsing. With enough power to take a mountain down everything was destroyed leaving nothing but rubble and ruins at the center of the battle for the world. No evil minions, no allied armies, no lingering doubts as to whether the battle was over.
In the final moments though the wailing and screams of an unimaginable amount of souls, magically bound to become an undead army, collapsed into a single point. Summoning what the runes had been damaged to crudely interpret as a 'one dead army' for a brief moment stood the one dead. Then they too were consumed in the collapse of the building leaving the area into the final darkness of the war, and the first darkness of the one dead. For them, everything had been chaos and eternity. Peace and nothingness. The power of the magic ripping their soul and countless others into the void of magic and plying them into the rules of the spell and the circle. Now that it all stopped here they lay amidst a different type of all-consuming darkness and pressure. Crushed into broken bits and dust they remained where they were summoned, in a state as close to slumber as someone already dead could be.
Time passed but the darkness did not. The broken and powdered bones slowly reformed into the shape of the one dead. The haze and fog of death, undeath, and the void slowly released the mind as one consciousness awoke. At the same time, the one dead's first dark finally ended as a dim purple glow lit behind his eyes and he started to get a sense of himself. The purple light illuminated his surroundings, which were not much, and he shifted. With him shifted the rubble and the first movement of the ruins happened since the day of its final collapse. With aches and grogginess more akin to sleeping too long after a long night drinking, the one dead moved to look at himself and where he was. His body was originally that of a recently dead man but now after all this time, he was merely bones. Dust fell past his vision as the chunks of the old room ground and pushed to make room for his movements. Everything was cast in a purple light that slowly grew brighter as did his consciousness.
At the end of a slow awakening, the one dead wanted a way out. With the bits of building pressing against him from all sides, he used the falling dust to figure out which way was up. Steadily he began to push and pull at the world around him, clawing his way up and out. Moving through the stone and metal was an ordeal. With every movement, he ground himself down, only for it to build back up on his immortal shell. At first, it was like a burning pain, a searing of flesh if he had any, but as he felt it endlessly he became used to it. Literally being worn down by the dig out, he began using his body to his advantage. At spots that were too small for him to fit, and the pieces too big to move, he began grinding himself down and pushing the parts of him through smaller openings than would be possible. He then slowly reformed and recollected himself on the other side as he dug. Ever climbing, pushed less by a desire to be free and in the open, but more for a desire to complete a task. There was no need to think or wonder as he dug his way out. Not about who he used to be or why he was here. Not about where here was or what he was meant to do. There was just the task set forth to move forward and get out. Determined and single-minded the task was all there was, and thus the one dead army marched onward with it.
All while he dug the glow of his eyes grew brighter, letting him see more and with finer detail. He learned how to see the shifting of the stones, their weaknesses, and the best path forward. Over an endless task, he toiled and eventually the purple of his surroundings faded even though his will did not. Eventually real light broke through, just as he broke out, and the first dark came to an end. It was not over until he was completely free though so he pushed stone and dirt away, clearing space for his body to be pulled out, some parts in pieces to be left to rejoin him as he reformed. Then the task was over and the one dead sat atop a mountain of ruins and rubble. An amalgamation of the past war and the time of nothing that passed since. Parts stuck out and had some shape of what they use to be, while others were nothing but ground rock becoming soil for the grass and weeds. The bright light of day just coming to an end lit up an expansive view around the one dead. Rolling hills and plains spread out around him, eventually leading to tall snow-capped mountains to the north, forests to the east and west, and what seemed like a river and marshland to the south. Looking around, this was the one dead's first look at the world he was brought to. Bits of bone dust slowly glided back to his arms and skull as he turned to look around him.
"That's one task done. What's next?" His voice sounded, quiet and if anyone was near they'd mistake it for the wind moving through the grass and plants. He had no body to hold air or throat to make sounds with. After so long of nothing this was not something he'd done before and thus was weak and untrained.
As the wind blew through the rubble and the one dead, the final summoning was finished and the purple glow fully settled into eyes that looked at the world, searching.