This episode is noted for being heavy on dialogue and exposition, adapting a significant portion of the Sword Art Online light novel (Volume 12, Alicization Rising ) to explain complex concepts like System Control Authority and the Taboo Index. It concludes with the two protagonists resolved to begin their literal climb through the Central Cathedral.

Cardinal explains her own existence as a sub-process of Quinella that split off when the Administrator attempted to expand her memory capacity by using another person's Fluctlight.

A small spider familiar belonging to Cardinal is introduced, having been observing the boys since their early days at the academy. Narrative Impact

Sword Art Online: Alicization Episode 13, titled serves as a pivotal lore-heavy episode that marks the end of the first cour and sets the stage for the ascent of the Central Cathedral. Episode Summary

Cardinal forms an alliance with Kirito and Eugeo. She reveals the truth about the Integrity Knights —that they are not legendary heroes summoned from the heavens but humans whose memories have been stolen and replaced by "Piety Modules".