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.
One-Way Crossover: ZZZ visits the Astral Express
According to HoYoverse, this is a one-way crossover; Zenless Zone Zero characters will appear in the world of Honkai: Star Rail, not the other way around. The developer has not yet announced the specific ZZZ characters that will be featured, but confirmed the event will officially launch in Winter 2026 (estimated to be around December to February of next year).
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 system, Road of Memories) 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 Desire), the surfer uses beach volleyball in combat, accumulating Punchline and Fervor to activate extended Elation Skill attacks.
- Crossover HSR x ZZZ: Launching Winter 2026, one-way (ZZZ → HSR)
- Update 4.5: "To Roll the Stars in Astropolis", released August 26, 2026
- New Characters 5★: Robin • Summeretto (Flower), Aventurine • Waveflair (Quantum)
- Background: Planet Planarcadia, after the victory against Lord Ravager Asat Pramad