Nazarick x Christmas (ナザリック×クリスマス) was a holiday event hosted by the denizens of the Great Tomb of Nazarick for their master Momonga. It lasted from December 18, 2019 to December 28, 2019. The event was re-released on December 15, 2020 to December 28, 2020.
Momonga began look for opportunities to go through diplomatic channels. Albedo witnesses him practicing his greetings, wearing a "Mask of Envy" to hide his appearance as a skeleton. Then she asked――what exactly is "Christmas"?
Momonga who was shifting through his Item Box found his Mask of Envy. Speaking out loud, he reminisced how he received this event item during Christmas in YGGDRASIL. Wearing the mask he found he could hide his skeletal features and began practicing his acting for his role as the ruler of Nazarick. Albedo who had barged into his room, thinking he was in trouble, thought the mask wearing Momonga was an intruder until the player revealed it was just him. Apologizing for her interruption on his attempts to inflirate human society, Albedo begs a a question on one of the words he mentioned. The specific word she is interested in is "Christmas." Momonga not wishing to disappoint her on the holiday told her Christmas was a day of celebration for the coming of winter. In that winter is the season when most creatures get around, that is, the season when darkness and death become more sensible. And when a Christmas party is held for close friends and family. Albedo taken by the holiday festivies, vaguely remembered in her memories of the Supreme Beings hosting a Christmas party, wishes to hold one in Nazarick. Momonga was intrigued by the idea and at the insistence of the Overseer Guardian, permitted her allow her to organize the festivities.
Later Albedo gathered the Floor Guardians and Pleiades to explain her plan. Doing her own research from Ashurbanipal she discovered that in order to have a Supreme Christmas Party, three items were needed: a meat dish, a Christmas Tree, and a Christmas cake. The NPCs were given ten days to acquire the necessary items. For the tree, Demiurge volunteered to acquire one. Sebas Tian and the Pleiades were assigned to take care of the Christmas cake, believing that they were confident to create it so long as they had the recipe. For the meat dish, though it was recommended that a chicken dish was most popular poultry dish for a Christmas feast, Albedo desired for something more exotic for Momonga's party. The protagonist, Slimeko and Narberal Gamma were assigned to locate suitable meat worthy of Momonga. Since nothing in Nazarick fitted the bill, the trio went to E-Rantel to do some research. On the way the group encountered stray Chaos Beasts but managed to reach the fortress city without any problem. Knowing that the human meat market was inferior to whatever Nazarick could produce, the trio instead went to the Adventurer's Guild hoping the adventurers' there would have information on exotic meats. Two adventurers did have some information, pointing out venison to be a superior meat, especially peryton. From one of the adventurer's own experience the meat from such a beast was unmatched. Additionally what caught the interest of the three agents was a rumor of a white peryton living somewhere near the Great Forest of Tob.
Upon returning to the Great Tomb of Nazarick, the agents reported to Albedo of their findings, who was thrilled at the discovery. She authorized them to capture the beast, alive preferably so as it could be butchered at the dungeon. To assist them, the protagonist asked the assistance of Shalltear Bloodfallen, as her abilities could make the capture of a peryton useful as well as draining its blood of impurities. Albedo agreed to the request as the three went to the Tob Forest to solicit Hamsuke's help. For the matter of getting Shalltear's help, Albedo proposed the idea to the vampire at the 10th Floor during a Chaos Beasts subjugation session. Shalltear found it amusing that Albedo would come to her asking for help. Albedo admits that Shalltear's skills in blood removal would be an assist acknowledging that the vampire's skill was shown through her superior Gigant Basilisk Gibier Steak dish. Though annoyed, Albedo is willing to ask her rival for help. Shalltear is approves of lending aid to the protagonist as soon as her business is done in cleaning away all the monster emerging from the Crack.
Outside of Nazarick Demiurge is making preparations for the Christmas tree. He is later joined by Aura Bella Fiora and Mare Bello Fiore at a patch of treants that are being cultivated. These treants were grown from the seeds harvested from the Supreme Odor Flower which was taken during Nazarick's Supreme Hanami. The demon used them in an experiment and created different strains of treants originally to create an army for Nazarick.
Demiurge selected one of his treants for the event, though Aura and Mare noted the specimen to be small for its kind. Evil Lord Wrath proceeded to release a human captive into the glen of treants. The human thief thinking he was freed attempted to escape only to have the treant drain him of his vitals. After the monster drained the human it fed on, it quickly grew into an evergreen conifer treant. The treant, however turned aggressive and attacked the group, forcing them to get it under control. After it was subdued, Demuirge had it transported to the 6th Floor by Aura and Mare. There they find Sebas Tian getting the Amphitheater ready for the venue. The butler is surprised by the treant and politely requests the elves to move the tree elsewhere while the venue is being set up. Mare complies and wishes to return to his patrol with Shalltear that is scheduled for the next day, though is informed by Sebas Tian that Shalltear has been reassigned to assist the protagonist and his team. After being told that the meat dish party would be heading to the Tob Forest to meet Hamuske, Aura become worried that her subordinate would be a bit overwhelmed by Shalltear.
At the forests, Hamsuke happily greets the protagonist and his team. Once the hamster is introduced to Shalltear and their mission, Hamsuke informed the group that she had indeed seen creatures matching the descriptions of perytons. She offers to be their guide to take them to where the monsters occasionally feed when they come down from the neighboring Azerlisia Mountains. The portagonist asks if Hamsuke ever seen a white peryton in the area, though sadly the Wise King tells him that she had only seen brown colored ones.
They are led to a clearing but they found nothing until a shadow high above the sky blocked out the sun. Narberal thinking it was a peryton flew into the sky to investigate, but it turned out to be a vulture. The bird attempted to attacked Narberal, but the combat maid swiftly dealt with it causing it to fall atop of Hamsuke. After the bird crashed into the ground, other vultures were found, and even the corpse of a deer. Seeing a vulture attempt to fly with the deer's corpse, the group believed that Hamsuke had mistakenly took it for a peryton. Though blame falls on Hamsuke for her poor guidance, the protagonist suggested they look toward the mountains to hunt for their quarry. It was agreed that they would hunt again the next morning.
Albedo also requested the aid of Pandora's Actor for Christmas decorations for the party. The Area Guardian, after his previous actions in retrieving swimsuits for the Pleiades had already been working on organizing the costume items of the Treasury, had accepted the task. Remembering an item in the inventory, he shows her the Christmas Costume which amazes her as it has the word "Christmas" in it. While he himself is unfamiliar the word, as his master refrained on telling its importance he surmises that it is a dress only to be used on the holiday. Taken by the dress Albedo wishes to wear it to impress Momonga and hopefully finally win the title of Princess. Pandora's Actor agrees and the two work together to prepare the proper decorations and dress for Momonga.
At the cantina, the Head Chef provided his expertise with the some of the Pleiades assistance to make the Christmas cake. There was a setback when Solution Epsilon used her own fluids for the acidic ingredients of the cake, instead of lemon juice, but the maids led by Yuri Alpha managed to stay on track. They fit another hurdle when they ran out of chocolate along the way as Lupusregina Beta had eaten most of it causing Yuri to be annoyed and chase her for her antic. Their commotion is heard all the way to the 6th Floor, where Entoma Vasilissa Zeta, CZ2128 Delta and Cocytus are patrolling. Despite the other two maids wanting to help make cakes they understood that patrolling the dungeon is equally important. The trio resume their duties in guarding the forest from the encroaching Chaos Beasts.
For the upcoming party, Yuri and her team had prepared at least ten cakes, using ingredients like cream, chocolate, and sponge cake from the stocks in Nazarick. The first cakes produced by the maids however were originally for decoration. Sebas Tian came to provide his viewpoint that even though he did not have a Cook class and he could help the women in harmonizing the display and taste to enhance their desserts.
Back at the Amphitheater, Momonga went to the venue where the party was getting ready, and when he saw the sight of Christmas party, he was impressed. Still thinking about how he can help, he bumps into Mare. He then takes teh opportunity to invite himself to join Mare's patrol with Aura to eliminate Chaos Beasts in the 6th Floor. As he says, Christmas is a family celebration and as a member of my family, he thinks they should prepare the venue together as it should be.
The next morning the group hike the mountains finding sparse vegetation and rocky terrain. They manage to spot an injured peryton, however, when they attempt to approach it they were attacked by vultures. Killing the vultures had allowed the peryton to escape, and it was deduced that the scavengers had a symbiotic relationship with the perytons.
The group tracked the injured animal to a cave where to their surprise several Perytons and the rumored Pure White Peryton was. Shalltear prepared to use [Paralyze] to subdue the Pure White Peryton, and entered the cave using [Perfect Unknowable]. A problem occurred as the Pure White Peryton is surrounded by normal perytons and thus she is unable to get any closer. Undeterred Shalltear attempts to use [Paralyze] but causes the perytons surrounding the leader to panic and fly out of the cave in a rush. Narberal uses [Electrosphere] to attack the perytons to prevent them from escaping. The Pure White Peryton appears from the hole with Shalltear in pursuit, she orders Narberal to target the small fry while she deals with the leader. After many of its subordinate perytons fell before Narberal, the Pure White Peryton was aided by a flock of vultures but Narberal simply uses [Electrosphere] to eliminate them. Without its allies Shalltear uses [Paralyze] and the beast is quickly captured. It was then taken back to Nazarick, where it was properly drained and butchered for the Christmas feast.
A gorgeous and cheerful Christmas party goes on without any interruptions, hosted in the Amphitheater of the 6th Floor. Momonga looking at the decorated Christmas tree, beautifully decorated Christmas cakes, and party dishes cannot help but be impressed by the work of his subordinates. He thanks Albedo for her efforts in organizing the event, who has dressed in a Christmas Costume for Momonga. Though he is briefly embarrassed he recovers and tries to delicately handle this. His acceptance of the outfit causes Albedo to bring up the final decision of the Queen War. She tries to promote herself as being the most worthy as his bride, though Momonga reminds her this event is a time for family not personal agendas. Feeling she misspoke, Albedo apologizes, but soon her spirits are lifted after Momonga begins giving out gifts to each of the Floor Guardians from his Item Box. Afterwards as the party begins to die down, Momonga seeing his Floor Guardians enjoy themselves decides to add to the festive atmosphere and uses his Super Tier Magic [World Change] to create snow much to the delight of the party guests. Briefly while watching the faces of the NPCs, they overlaps with the memories of Momonga's old guildmates, making him feel sad. The feeling is however replaced by warmth of the family he has gained since coming to the New World, and continues to enjoy the last moments of the Christmas holiday.