Two of gaming's biggest franchises HoYoverse officially shake hands: Honkai: Star Rail and Zenless Zone Zero will have its first crossover, released on Winter 2026. This signal was hinted at in a previous update of ZZZ, when the mechanical bird Pom-Pom appeared at the Video Store run by Wise and Belle.
ZZZ Characters Visit the Astral Express
During the Version 4.5 special program on August 14, HoYoverse said characters from the world of Zenless Zone Zero will join the Trailblaze, which makes Honkai: Star Rail the host of the visitors from ZZZ. The developer had not yet named the characters then, but confirmed the event will launch in Winter 2026 (estimated to be around December to February of next year). In late September, the Version 4.6 special program revealed that Ellen and Astra Yao from ZZZ will appear in Honkai: Star Rail Version 4.8.
Ahead of the crossover: Update 4.5 has a summer theme
Before the crossover happens, the Astral Express train will get its own "beach special episode" in the update 4.5, "To Roll the Stars in Astropolis", expected to be released on August 26, 2026. The plot follows the fleet's victory over Lord Ravager Asat Pramad, bringing the otaku planet Planarcadia to face an unexpected crisis.
Two 5-star summer recruits
The update introduces two 5-star characters with completely new summer looks: Robin • Summeretto (Wind, Path of Remembrance) brings squad buffs through the Vibes and Fever Pitch mechanics, along with the new single "Only by Chasing the Wind"; and Aventurine • Waveflair (Quantum, Path of Elation), the surfer uses beach volleyball in combat, accumulating Punchline and Fervor to activate extended Elation Skill attacks.
- Crossover HSR x ZZZ: Launching Winter 2026; ZZZ characters join HSR (the reverse direction is not confirmed)
- Update 4.5: "To Roll the Stars in Astropolis", released August 26, 2026
- New Characters 5★: Robin • Summeretto (Wind), Aventurine • Waveflair (Quantum)
- Background: Planet Planarcadia, after the victory against Lord Ravager Asat Pramad
Where the crossover was announced, which way it runs and what is still missing
According to outlets relaying the announcement, the crossover was first teased on 17 July 2026 during the Zenless Zone Zero Version 3.1 “The Long Goodbye” special program, then repeated from the Honkai: Star Rail side in the Version 4.5 program on 14 August 2026. The ZZZ account posted a note styled as a bug report: after a “technical evaluation”, the team said it could not yet fix the bug where Pom-Pomboo suddenly appeared on Sixth Street, so it decided to hold a full collaboration event instead. Per AllThings.how, players can interact with Pom-Pom at several spots, mainly around the Random Play Video Store.
What is settled: the crossover runs in Winter 2026, ZZZ characters will appear in Honkai: Star Rail (Ellen and Astra Yao are set for Version 4.8), and no specific date has been announced. On the reverse direction, sources disagree: TechWiser and AllThings.how describe it as two-way, GenshinBuilds does not state a direction, and the HoYoverse announcement OtaHub could read only says ZZZ characters join HSR. Do not treat either one-way or two-way as final.
On the HSR side, Ellen and Astra Yao are now confirmed by HoYoverse for Version 4.8; Robin visiting ZZZ remains a leak and is not confirmed. If you want to prepare resources, wait for the special program of the version that carries the crossover rather than saving up on rumors.
