Honkai Star Rail recently shared compensation details via their official X account, for extending the duration of version 3.8 as well as sharing some teasers for the new world coming in version 4.0 and possible upcoming characters. These previews now give the community an idea of what to expect in the next major regional update, especially since the dev team has been reworking it's original concept.Players have also noticed that this region which was once called Edo Star in-game, has now been officially renamed to Planarcadia. Here’s a breakdown of the teasers, possible character lineup and possible lore tied to this new region coming in version 4.0.Note: The following information is based on the author's analysis and is also subject to change as more official information arrives. Readers are advised to take it with a grain of salt.Honkai Star Rail's version 4.0 Planarcadia teasers explainedHonkai Star Rail announced via their official X account that version 3.8's longer 8 week schedule is because the developers are still working on the regional design for version 4.0.The teasers shared so far suggest how the new region has cyberpunk visuals and arcade-style elements. It also seems to feature amusement-park themes that give the region a playful vibe, fitting well with the Aeon of Elation’s spontaneous and carefree personality. In the additional information provided by HoYoverse, the Astral Express had once crashed and departed from this planet in the past where the crew was given a chance to be an Aeon for a minute.Some players in the community also speculate that this planet could be Himeko's home planet, as her character story talks about how the Express once crashed there in the past as well.Renaming from Edo Star to PlanarcadiaThe redesign of the new region comes after the original Edo Star concept was scrapped, likely due to ongoing political tensions between China and Japan. The developers had initially planned this concept as a cyberpunk setting with clear Japanese-inspired elements in its environment and character lineup for almost a year.Now it has been renamed Planarcadia while keeping the cyberpunk theme, with brighter arcade-style colors and a playful, stylized and comical layout that fits the tone Edo Star was meant to have. This direction seems to fit Honkai Star Rail’s overall game design and also lines up well with Aeon of Elation, Aha's personality.New possible playable versions of familiar charactersAnother teaser showed upto six character silhouettes that every player in the community are currenlty trying to identify. So far, they likely resemble with the silhouettes of familiar characters like Sparkle and Blade while the others are currently unfamiliar. HoYoverse has to yet to confirm the lineup and will likely reveal by the time Honkai Star Rail's version 4.0 comes close.The estimated release window for version 4.0 is probably by end of February to early March 2026. This will give the developers enough time to refine and rework version 4.0, ensuring players have a polished and enjoyable experience at launch.These early teasers of Planarcadia, featuring arcade-style visuals, new possible versions of characters, and a fresh design direction, have raised expectations for many players across the community. With the developers taking their extra time with version 3.8's 8 week schedule, players are hoping this wait pays off once Honkai Star Rail version 4.0 arrives.