In an alternate timeline set 200 years before the events of the main light novel. The Elder Coffin Dragon Lord also known as Cure Elim had turned itself into an undead as part of it's preparation to gain more power and in doing so, absorbed the souls of numerous nations around it's location. It turned all living beings into mindless undead, at the same time where in the nation of Inveria, a young Keno inadvertently triggered her talent and copied the same racial change spell that Cure Elim had casted. As a result, all the citizens of her nation were also turned into undead too.
Suzuki Satoru in an effort to pinpoint the source of the calamity had tracked the center point of the undead convergence phenomena and it lead him to Mount Keitenias and in doing so, encountered the source that turned out to be the aforementioned Dragon Lord. This resulted in Suzuki Satoru to confront the Dragon Lord in order to avenge the suffering his friend went through cause of the Dragon Lord's actions.
In order to prepare what sort of opponent Suzuki was going to fight against, he took some precautions in order to properly assess the opponent's abilities as well as to make sure not to show all of his cards yet in order to lure the opponent into a false sense of security.
As he marched towards the mountain, Suzuki followed a trail of bones till he reached the source which was a massive pile of undead all piled up together into one giant ball. After initiating a few taunts to his opponent, it finally made its move and revealed itself in their full glory.
Now facing an opponent that could potentially beat him, Suzuki took the appropriate action against him. The Dragon Lord did not bother to give Suzuki any attention until it was constantly provoked and badmouthed several times much to his annoyance. After some provocations from the latter, the Dragon Lord decided to indulge the undead and toy with him, using him as a way to test his powers he had acquired. Upon exchanging a few blows, Suzuki was ensnared by the zombies that Cure Elim was controlling. As the Dragon Lord was about to finish him off for good, that was only until Suzuki used a sealing crystal to escape Cure Elim's clutches.
Once Suzuki understood who he was facing and what kind of foe it is, he step back into the battlefield and challenged the Dragon Lord for a second round. However, this time around, Suzuki brought with him his guild weapon and the appropriate equipment to effectively deal against him. While the Dragon Lord was caught surprise by his change in attitude and gear, Cure Elim set up the Wild Magic Spell known as World Separating Wall to ensure that Suzuki no longer have an escape route to get out of. When Suzuki used his ultimate skill [The Goal of All Life is Death], it forced all of the zombies he was controlling as a meat-shield armor to immediately die off. At the same time, he ended up conjuring forth several Dark Youngs out of the many sacrifices to surround and entrap Cure Elim simultaneously. This in turn, left Cure Elim completely exposed to the following combo initiated by both Suzuki and the Staff of Ainz Ooal Gown's powers. As a result, the Dragon Lord received a magical bombardment of attacks from many powerful tier spells and high-tier elemental summons, forcing Cure Elim to reveal his trump card he had kept hidden until this moment. He used such trump card to wipe all that is in sight of him but Suzuki was left unharmed due to the protection of a World Item he has equipped with.
Perplexed, they continued to exchange more blows till Suzuki revealed that he also brought along the members of Corpus of the Abyss into the fight without the Dragon Lord noticing. Caught off-guard by the blasts of multiple spells from these undead liches as well, it enrages Cure Elim to the point that he casted his trump card once again for the second time that only wiped everything out except for Suzuki who still remains unscathed. With the Dragon Lord's Wild Magic and health continue to steadily deplete and almost at the end of its life, Cure Elim was forced to go out of his way and cast Tier Magic spells. Cure Elim initially had no intention of relying on that power it hated until its life was in peril. The Dragon Lord use that power to act as its last line of defense, defending and attacking Suzuki. However, by than it was already too late for the Dragon Lord to have a comeback. Due to one final blow from Suzuki which finally chipped its health down to zero, Cure Elim disintegrated and crumbled to ashes. Before the Dragon Lord met its inevitable death, Cure Elim's last breath of words were directly thrown at the disdain player, cursing the very being that lead to his downfall.
After the Dragon Lord was defeated, both Suzuki and Keno returned to see if the his death had resulted in the citizens and her parents to change back to normal. Sadly this was not the case, but Suzuki vowed that he would still do everything within his power in order to bring them back. Although Keno thanked him, deep down both of them have already started to accept the fact that it will most likely never going to happen. Suzuki was still bothered by that train of thought but took some comfort in knowing that the entity responsible for the mess was taken care of. He figured that Keno has now started to come to an acceptance, knowing that her nation was at least avenged.
- While Cure Elim was killed in the alternate timeline, It is currently unknown if he is either dead or alive in the current timeline.