The Short Version
Netmarble opened pre-registration on September 14, 2026 for a collaboration between its collectible RPG Seven Knights Re:BIRTH — developed by Netmarble Nexus — and the anime Demon Slayer: Kimetsu no Yaiba. It pairs a proven mobile RPG with one of the world's biggest anime IPs, making it a headline crossover for the autumn mobile season.
The collaboration runs four weeks, October 1 to 29, and is built around characters from the film Demon Slayer: Kimetsu no Yaiba – Infinity Castle, Chapter 1. Every pre-registrant receives 10 Demon Slayer Summon Vouchers, and players can claim Tanjiro Kamado just by logging in during the event.
Sources: Final Weapon — Seven Knights Re:BIRTH x Demon Slayer collaboration · Inven Global — Legendary Tanjiro and Nezuko pet incoming · Netmarble official collaboration page
Schedule and Rewards at a Glance
| Item | Detail |
|---|---|
| Pre-registration opens | September 14 (special landing page) |
| Pre-registration closes | Before the October 1 update |
| Pre-reg reward | 10 Demon Slayer Summon Vouchers (all participants) |
| Collaboration period | October 1 – 29 (4 weeks) |
| Login reward | Tanjiro Kamado (claim by logging in during the event) |
| Gameplay reward | Legendary Pet Nezuko Kamado · collab heroes |
The main pre-registration hook is the 10 Summon Vouchers. They can be spent directly on collab-hero summons, so simply registering puts you at the starting line for the crossover roster. Add the login-reward Tanjiro and the gameplay-reward Nezuko pet, and the event opens a wide free path to the collaboration's signature characters.
Two Updates — Four Heroes Join
The collab heroes arrive across two October updates, drawing on the key figures of the Infinity Castle film's first chapter.
| Update | Heroes joining |
|---|---|
| October 1 | Tanjiro Kamado · Zenitsu Agatsuma |
| October 15 | Shinobu Kocho · Giyu Tomioka |
Tanjiro is a Special Legendary-grade hero, handed out free to anyone who logs in after the first update. From there, gameplay lets players earn the Legendary Pet Nezuko Kamado and the remaining collab heroes. Leaving so many free acquisition paths open reads as a design aimed at new and returning players alike.
Background: The Game and the Anime IP
Seven Knights Re:BIRTH carries forward Netmarble's flagship Seven Knights IP as a collectible RPG. Built on character collection and turn-based combat as a live-service mobile game, it is playable on iOS and Android, as well as PC via the Epic Games Store.
Its partner, Demon Slayer: Kimetsu no Yaiba, is a mega-IP whose original manga by Koyoharu Gotouge has surpassed 220 million copies in circulation. This crossover leans specifically on the Infinity Castle film, tying the anime's freshest moment directly to in-game content.
Impact and Market Analysis
The collaboration's center of gravity is timing. Infinity Castle, Chapter 1 drew major attention in theaters and is now expanding to streaming, with a large fan base worldwide. Putting the film's characters straight into the game as playable heroes is a powerful hook for converting anime fans into new players.
For Netmarble, the tie-up is a card played to defend autumn live-service revenue and win back lapsed players at once. The free ladder — summon vouchers, login reward, gameplay reward — widens the user base, while collab-limited enhancements and cosmetics carry the monetization, a familiar live-service playbook.
Community Reaction
Early reaction has been broadly positive. The free-acquisition elements — "Tanjiro just for logging in" and the "Nezuko pet" — landed especially well. On the other side, some players are cautious about the performance and gacha rates of the collab-limited heroes and the relatively short four-week window.
The key variable is the actual October 1 and 15 updates. How Shinobu and Giyu perform and present after Tanjiro and Zenitsu will shape early sentiment. Locking in the pre-registration vouchers and login rewards ahead of the update is the smart move.
GamePeak Bottom Line
| Point | Summary |
|---|---|
| What | Seven Knights Re:BIRTH x Demon Slayer collaboration |
| Pre-registration | September 14 – before the October 1 update |
| Pre-reg reward | 10 Summon Vouchers (all participants) |
| Collab period | October 1 – 29 (4 weeks) |
| Heroes | (Oct 1) Tanjiro, Zenitsu · (Oct 15) Shinobu, Giyu |
| Free path | Tanjiro on login · Legendary Pet Nezuko through play |
| Platforms | iOS · Android · PC (Epic Games Store) |
Seven Knights Re:BIRTH enters the autumn collaboration race on the back of a global anime juggernaut. With a wide free-acquisition path lowering the barrier to entry, fans of the source material have good reason to pre-register and secure the summon vouchers and Tanjiro line early.