Undead Unluck episode 18 came after the majorly shocking twists of episodes 16 and 17. It involved Juiz being asked several different questions about the truth of everything on the show. The first few minutes were flashbacks to everything: all of the foreshadowing leading up to the ultimate answer and the truth of everything in Undead Unluck.
Juiz decided to reveal everything she knew about the world, including the true nature of The Union, Juiz's Negators, the Quests, and the barrage of memories that Fuuko received in episode 17. Undead Unluck episode 18 finally opens the floodgates and exposes the true story, in the episode titled Cry for The Moon.
Undead Unluck episode 18: The Loop and the true story explained
The Loop
The first major thing revealed about the story in Undead Unluck episode 18 is The Loop. The world has been on a loop for some time, a large time loop of death and renewal that God has subjugated humanity and all life to. The world explodes, and everyone and everything dies. There is no escape from that final death; not even escaping into space will avoid that death.
Then, a new world is formed, and the cycle repeats. Undead Unluck episode 18 has Juiz answer many questions that Andy, Fuuko, Shen, and the audience have. Including what proof there is of the Loop, how she knew Victor, and that the Union was created to stop the constant cycle of destruction and renewal.
The Proof
The claim has plenty of proof, as Undead Unluck episode 18 displays. The first bit of proof that Juiz offers is how the world begins and ends: God destroys the Earth by blowing it to bits, and sometimes those bits are turned into a fragmented asteroid belt around the new Earth. This contradicts how meteorite formations are taught in school, as Fuuko chimes in.
Examinations of the meteorites Fuuko called down during her massive Unluck Events before the addition of the UMA Galaxy show heavy anomalous properties and an absurd makeup in the rock. The other couple of bits of proof is Andy having a mole at the back of his right ear, which Fuuko confirms to her embarrassment. This hints at Victor and Juiz being close.
The Ark and Fuuko's Kill la Kill homage
In a shoutout to Kill la Kill's Mako Mankanshoku's speeches, where Mako interrupts whatever is going on to either inspire Ryuko Matoi or give a speech that sounds completely random to anyone else but her, Fuuko freaks out and starts speechifying to absorb all the information in the same silly style.
The Ark itself isn't fully explained yet as of Undead Unluck episode 18. However, what is known about it makes it easy to extrapolate its purpose: the storage of events from previous loops. What Billy may want with it is unknown but easy to guess: an advantage over The Union, Juiz, and a way to kill God and survive or otherwise manipulate things if he fails.
The two that remember
Only two people remember the Loop: Juiz, who's been using Ark to compliment her memories, and Victor, who's existed since Death became a Rule. Even if the Loop destroys the whole planet and kills everyone on it, Victor and Andy will not die at all.
Shen's calling out of Juiz and Victor's familiarity with each other wasn't off the mark at all. They knew each other because they were the only two who remembered the Loop and worked together.
When Fuuko asks if they were romantically involved, Juiz says it was ancient history, and Andy doesn't remember. The first ED showed Andy waking up from a dream about someone who looked identical to Juiz; that might've been foreshadowing.
The resolve and the new missions
After stating that she finally managed to get Negators that could kill God in the current Loop, Juiz said that Billy's insurrection was an error fully on her part and that she'd gladly end her life to atone for it. Still, absolutely nobody accepts that statement or bows to them in supplication.
Everyone rallies around Juiz, planting another Roundtable made of Stone that's hand-etched into the ground and gathering around it to resume their meeting. Their new missions are thus: complete Apocalypse's Quests before the deadline, ascertain the location of Under's base, stop Billy's possible nuclear weapons plan, and take any stolen Artifacts and their Roundtable back.
Oddly, Juiz also assigns Andy and Fuuko some reading to do since the situation has passed beyond her knowledge. Undead Unluck episode 18 ends with Juiz pulling out a manga that Fuuko seems to recognize. According to Juiz, this manga seems to be the key to moving forward, with the next episode preview teasing that it seems to be the manga Fuuko was reading in episode 1.
Final thoughts
Undead Unluck episode 18 is more of a breather like episode 15 was, except on an entirely different level than the aforementioned episode. Episode 15 previewed the rest of Under, premiered their name, set up the gun Artifact, and gave Chikara's backstory and his official joining the Union.
Undead Unluck episode 18, on the other hand, answers a lot more questions, such as why Victor and Juiz seemed familiar with each other, the significance of the memory attack on Fuuko in episode 17, and Billy's cryptic line about having 'Tens of Thousands of tries' in episode 16.
Undead Unluck episode 18 will probably go down as yet another major turning point; the story's true nature is revealed, and things start to escalate on another level. While it might feel like a clip show episode due to the overabundance of flashbacks to relevant moments, Undead Unluck episode 18 still makes all of that count with this turning point.