Honkai: Star Rail (HSR) is preparing to leave Planarcadia behind, and the Astral Express has quite the destination in mind. HoYoverse has revealed the first details for Version 4.5 in their recent livestream, which will send the Trailblazers to Astropolis, introduce two new limited 5-Star characters, and, perhaps most importantly for fans of Zenless Zone Zero (ZZZ), finally confirm that characters from New Eridu are coming to HSR.
There’s a lot going on in Version 4.5, but the crossover announcement is one the most intriguing parts of the livestream for ZZZ and HSR players alike. We now know that the two games are officially crossing paths later this year, and it’s not the one-way street it was originally implied to be.
Heading to Astropolis
For Version 4.5, the story picks up after the Express crew’s victory over Lord Ravager Asat Pramad, but the celebration isn’t going to last very long. The Voracity has arrived on the scene, throwing Planarcadia into another crisis and forcing the Trailblazers to look elsewhere for the power needed to save it.
The search will take the crew to the wonderous Astropolis, home of the Interastral Peace Entertainment. Rather than simply walking into the headquarters and asking for help, however, the Trailblazers will have to navigate the organization’s famously complicated management structure to get what they need. With Planarcadia in a new crisis, Trailblazers will have no choice but to make something happen.
There should be plenty of time for something a little more fun, too. The Trailblazer will get to enjoy an interstellar vacation alongside fan-favorites, Robin and Aventurine, giving Version 4.5 a chance to mix its latest cosmic crisis with some considerably less stressful sightseeing. Considering how much Asat Pramad pressured the Astral Express crew, a small break is probably much needed.
Robin and Aventurine weren’t just mentioned for show. Brand-new versions both characters is coming in Version 4.5. 5-Star Robin Summeretto arrives as a Wind Remembrance character, while 5-star Aventurine Waveflair joins as a Quantum Elation character. Both characters make their return with completely different elements and roles. Hyacine and Ashveil will also appear in the Version 4.5 Warp events as reruns, with Hyacine featured in the first half of 4.5, and Ashveil following in the second.
Zenless Zone Zero Crossover Confirmed!
Now for the really juicy part. HoYoverse has officially confirmed that Zenless Zone Zero characters will be making an appearance in Honkai: Star Rail later this year, meaning New Eridu is about to get considerably more cosmic. This comes after previous confirmation of the opposite: that HSR would be making a pit stop in ZZZ’s New Eridu.
The collab is set to begin Winter 2026 but, unfortunately, that’s where the details stop. HoYoverse hasn’t revealed which ZZZ characters are making the trip, or exactly what form their appearance will take. Still, this is considerably more information than we had just a few weeks ago, when HoYoverse first confirmed that the two games would collaborate without revealing what that collaboration actually meant.
For now, all we know is that ZZZ characters are coming to the Astral Express. Considering just how many memorable characters New Eridu has accumulated, figuring out who gets chosen may be almost as interesting as seeing what HoYoverse actually does with the crossover.
Honkai: Star Rail is Also Teaming Up With MOONDROP
The ZZZ crossover isn’t the only collaboration coming to Honkai: Star Rail. HoYoverse has also announced a partnership with MOONDROP, which will bring Sparxie-themed products and a variety of online and offline events to multiple regions around the world. More details about that collaboration will be revealed later, so there’s still plenty left to learn.
