Steam / Windows PC
Crossplay between all PC versions at launch.
Release
Kernel Hearts launched on 17 September 2026. Steam, Epic Games Store, Xbox Series X|S with Play Anywhere PC, PlayStation 5, and Nintendo Switch 2 all share that date in first-party or publisher materials. Steam’s US list price is $19.99. A public demo shipped 31 March 2026 and updated for Steam Next Fest on 15 June 2026. Buying the Epic copy grants a Fernet Fortnite outfit; the Item Shop date on that press note is 26 September 2026. Use the timeline below to sort those seven records by date or by platform name.
What each storefront actually claims
Steam is the numbered app 2902170 with English store copy, achievements, and the $19.99 US price. Epic is the Fortnite-outfit bundle and a PC SKU in the same-day launch set. Xbox adds Game Pass, cloud, Play Anywhere, and a TEEN rating. PlayStation 5 and Nintendo Switch 2 are confirmed by the launch trailer and the Whitethorn fact sheet rather than a scraped console API in this research set. PC install size on Steam is 15 GB. Minimum PC: Windows 10, i7-9750H, 8 GB RAM, GTX 1060. Recommended: i7-10700 or Ryzen 5 3600, 16 GB, RTX 2060 or GTX 1660 Ti.
The game began in a 2020 jam. Ephemera is an Argentine studio mixing Japanese and Argentine culture; Akira is Game Director, with support at akira@ephemeragames.com. IGDB lists Unreal Engine 5. Those studio notes belong here because they travel with the SKU, not with a Tower floor.
Whitethorn’s product page and the launch trailer are the Switch 2 and PlayStation 5 confirmations used in this table. If a regional SKU is missing from your storefront, that is a storefront problem, not a missing row this wiki will invent. Steam remains the achievement host even if you play elsewhere.
Demo, Next Fest, and Japanese VO
The Steam demo is app 4533500. It taught the two-floor climb and the lab backup. Next Fest on 15 June 2026 refreshed that demo. The final demo update added Japanese voice acting and requires a New Game for story scenes. Xbox Wire and Steam news are the sources for those dates; the demo is a two-floor sample, not the around-7-floor 1.0 height.
If you still have the demo installed, treat it as a tutorial SKU. The 1.0 save on Steam, Epic, Xbox, PlayStation 5, or Switch 2 is the product this wiki’s other pages describe. For co-op player counts and Game Pass, the shorter answers live on FAQ.
Next Fest on 15 June 2026 is why some players still have a demo build that is newer than March and older than 1.0. Check the demo’s news date before you judge floor count. Two floors is the demo. Around seven is 1.0. Mixing those numbers in a Steam review is how the floor fact gets argued; those dates stay attached to the demo and to 1.0.
Epic purchase and the Fortnite outfit
The Games Press note is the source for the Fernet Fortnite outfit: buy Kernel Hearts on the Epic Games Store, receive the outfit on the same account, then watch the Item Shop date of 26 September 2026. The platform table also records a 17 August 2026 Fortnite row. Those two dates are different events — a purchase bonus versus a shop window — and should not be collapsed into one “Fortnite launch” sentence.
PC crossplay at launch is a Steam news claim covering PC versions. Xbox Play Anywhere covers the Xbox SKU on console and that program’s PC path. They are not automatically the same pool. If you need a party across Steam and Xbox, wait for a later official sentence rather than assuming the two crossplay lines stack. Price remains $19.99 on Steam US unless a sale flag appears on that storefront.
The outfit is Fernet, the starter unit, not a random skin. Epic same-account purchase is the unlock path printed in press. Item Shop on 26 September 2026 is a later window for people who did not buy the game. Neither path is a Tower of Babel reward.
Order
Epic Games Store
Fernet Fortnite outfit with same-account purchase.
Xbox Series X|S + Xbox Play Anywhere PC
Game Pass, cloud, online co-op 2-4.
PlayStation 5
Confirmed by launch trailer and publisher sheet.
Nintendo Switch 2
Confirmed by launch trailer and publisher sheet.
Steam + Epic demo
Demo ~2 floors; full game around 7. Final demo update added Japanese VO.
Fortnite
Fernet Outfit via Epic purchase; Item Shop 26 Sep 2026.
Sources