Warning: spoilers ahead for Undead Unluck chapter 95!
Readers can no longer rely on the biggest twist in Undead Unluck, which revealed a major character has been traveling back in time every time she's failed to prevent God from destroying the world.
Way back in chapter 35, a leader named Juiz - in charge of a group of individuals with special powers known as the Union - revealed that she has gone back in time on a mysterious vessel known as the Ark every time she's failed to prevent God from ending life as they know it. Each time, Juiz has formed a more powerful Union to destroy this malicious god but has failed so many times that she recently revealed she only has enough fuel to go back once more. But after Union member Fuuko Izumo is fatally wounded, Juiz determines Fuuko is so monumental to the cause that Juiz uses the Ark to instead travel to a moment she knows will help them save her.
What Juiz is depending on is a game of sorts that Undead Unluck's God imposes on the Union every lifetime. This sadistically twisted god creates a system where the Union is forced to accept missions from a sentient book known as Apocalypse. The Union receives awards for each completed mission that can help them kill God, but every failure not only leads to a disaster they must contend with, but a stone materializes on a 101-slotted stone tablet, and when that tablet fills up, the world ends. Since Juiz has time traveled, she's aware that the reward for completing their last quest could help Fuuko live, but she doesn't know for sure since this is the first time that Fuuko has joined the Union in all of her attempts. The problem, however, is that Apocalypse will not give them their reward for another week, and since Fuuko will not survive those seven days, Juiz travels one week into the future to the moment when Apocalypse presents the possibly life-saving reward.
Juiz's actions both reinforce the importance of Fuuko's character and force mangaka Yoshifumi Totsuka to work within this particular timeline. Readers always had hope that even if God won and destroyed the world again, Juiz could still go back in time and try again. But now that she has no more fuel, this is her last chance. Of course, Totsuka has proven to be quite proficient in throwing curveballs, so this could always change, but as of now, this latest development significantly reduces the number of possible outcomes. And just like the previous fight that solely revolved around Fuuko, Fuuko is now clearly humanity's last chance in defeating God.
Juiz hinted at Fuuko's importance early on when she revealed that the asteroids Fuuko's Unluck sometimes summon are actually the remains of each of the worlds that have been destroyed by God, but now that importance is truly underscored. The next time the world ends in Undead Unlock, there'll be no escape, changing the stakes of the manga forever.