Mushoku Tensei Season 3 Episode 13 Preview: Fans Brace for the Diary Arc

Mushoku Tensei Season 3's official preview for Episode 13, "Diary," dropped September 18 from TOHO animation's channel, and unlike last week's preview, it's narrated in-character by present-day Rudeus rather than the older "Old Deus" persona who carried Episode 12's teaser.

In under a day the video passed 1,500,000 views and pulled in over 1,000 comments. The top reply (2,030 likes) credits the production team's restraint about spoilers, but another heavily-liked comment (1,308 likes) reads the preview as confirmation the anime is about to animate the diary material in full rather than compress it into a quick recap, and the comment section splits between anticipation and dread from there.

By the end of the thread, commenters are debating whether the tragic path shown here even counts as the story's "true" version of events, and whether Episode 13 is shaping up to be the best episode of the year or the most miserable one.

TOHO animation's channel dropped the official broadcast preview for Mushoku Tensei Season 3 Episode 13, "Diary," on September 18. Where last week's Episode 12 preview was narrated in-character by the older, future persona fans call "Old Deus," this one hands the narration back to present-day Rudeus, voiced by the same actress, Yui Uchiyama, just at a much younger point in his life. The video has already passed 1,500,000 views and 14,000 likes, and pulled in over a thousand comments in under a day.

The comment section isn't really arguing about the narrator switch, though. What's got people talking is how much of the diary material the preview seems willing to show. More than one commenter had assumed the anime would treat this part of the story as a quick digest and move on. This preview reads instead as a promise that it won't be rushed.

That promise is landing as reassurance and dread in roughly equal measure. Commenters are also picking the preview apart frame by frame for whatever details they can find, right down to a shot of candles being extinguished that more than one person reads as a piece of visual foreshadowing.

The comparison that keeps coming up is Re:Zero, whose time-loop mechanic gives that show's tragedies a kind of built-in reset button. Commenters point out Mushoku Tensei doesn't have that safety net here: whatever Old Deus goes through, it stays.

Some of that nervous energy turns into gallows humor fast, especially once people start comparing this stretch of episodes to how lighthearted the season felt only a few episodes ago, back when a much goofier subplot had everyone excited for something called "Perugius Land."

Underneath the jokes, a more serious argument runs in parallel. A few commenters read the tragic path Old Deus lived through as the story's "true" version of events, the sense fans use when debating Mushoku Tensei's branching what-if timelines, with this future version's experience standing in as the "real" outcome the main timeline gets measured against. Not everyone buys the theory as stated, and at least one reply points out a detail that complicates it if taken literally.

By the time the thread gets around to guessing whether Episode 13 ends up the best episode of the year or the most depressing one, nobody in the section is really arguing it has to be one or the other.