Recently, fans of miHoYo (HoYoverse) games noticed that Pom-Pom, the conductor of the Astral Express from Honkai Star Rail, another game by the studio, appeared in the world of Zenless Zone Zero.
Now miHoYo has officially confirmed that this was intentional — there will be a full-fledged collaboration, and this is just the first teaser:
Zenless Zone Zero and Honkai: Star Rail collaboration confirmed! Hello, Proxy! We regret to inform you: based on the results of the technical evaluation, we cannot yet fix the bug with the sudden appearance of "Pom-Pombu" on Sixth Street.
miHoYo published a promotional banner with the collaboration launch window in the official Zenless Zone Zero community:
The start of the Zenless Zone Zero × Honkai: Star Rail collaboration is scheduled for winter 2026. The developers have not yet revealed the details and promised to share more information in "future official announcements."
According to insider information, characters from Zenless Zone Zero will visit Honkai Star Rail. Allegedly, Astra Yao and Ellen Jo will appear in HSR 4.7; and Robin from HSR might be added to ZZZ. It is not yet clear whether they will be playable, or if it's just a cameo.
The release of Zenless Zone Zero 3.1 update is expected at the end of this month. Several new playable characters and more will be added to the game.