Seven Knights Re:BIRTH x Demon Slayer: Heroes, Dates & Rewards

Netmarble has announced a Demon Slayer: Kimetsu no Yaiba collaboration for Seven Knights Re:BIRTH, built around The Movie: Infinity Castle Chapter 1 — and it arrives in two waves rather than one.

Tanjiro Kamado and Zenitsu Agatsuma land on 1 October. Shinobu Kocho and Giyu Tomioka follow on 15 October. Two weeks apart, with a Legendary Nezuko pet alongside them.

Here's the full schedule and the planning problem inside it.

The short version

• Themed around Demon Slayer: Kimetsu no Yaiba The Movie: Infinity Castle Chapter 1.
• Four collaboration heroes across two updates.
• 1 October: Tanjiro Kamado, Zenitsu Agatsuma.
• 15 October: Shinobu Kocho, Giyu Tomioka.
• Tanjiro is a Special Legendary hero and can be obtained free.
• A Legendary Nezuko pet is included.
• End dates and banner structure haven't been announced.

The two-wave split is the real decision

This is the part worth acting on before 1 October.

Two updates, two weeks apart, with two heroes each. That sounds generous — twice the content, twice the chances. In practice it's a resource-management problem.

If Shinobu or Giyu is the one you want, you need to arrive on 15 October with currency intact. And the first wave is designed to spend it: two new heroes, a Legendary pet, and collaboration content all landing at once.

The risk isn't running out. It's running out at the wrong time. Players who pull heavily on 1 October and then see the 15 October lineup often find themselves short by a week.

Decide which of the four you actually want now, while none of them has a showcase trailer competing for your attention.

Don't assume wave one stays available

Here's a caution worth taking seriously, because nothing published addresses it.

Netmarble hasn't announced end dates for either wave.

And the precedent is short. Seven Knights Re:BIRTH's previous collaboration — with Solo Leveling — ran from 19 March to 2 April 2026, exactly two weeks.

If Demon Slayer follows the same rhythm, the first wave could close around the time the second opens, meaning Tanjiro and Zenitsu may not still be obtainable on 15 October.

That's inference, not information. But the safe assumption is that a wave-one hero is a wave-one opportunity. If you want Tanjiro or Zenitsu, treat 1 October as the window rather than waiting to see what the second wave brings.

Tanjiro is free

The headline reward, and an unusual one for a collaboration.

Tanjiro Kamado arrives as a Special Legendary hero and can be acquired for free. In a game where hero grade drives account value, giving away a Special Legendary collaboration unit is a significant offer rather than a token one.

The exact acquisition method hasn't been detailed in the announcement material — whether it's a login campaign, a mission track, an event exchange, or something else. Check the in-game notice when the update lands on 1 October.

Two practical consequences:

• Don't pull for Tanjiro if the free route covers him. Spending summons on a hero you'd have received anyway is the most avoidable mistake in any collaboration.
• Budget your currency toward the three who aren't free. Zenitsu, Shinobu and Giyu are where your rubies and tickets actually need to go.

Nezuko is a pet, not a hero

Worth flagging because it sets expectations correctly.

Nezuko Kamado appears as a Legendary pet rather than a playable hero.

In Seven Knights Re:BIRTH, pets are a separate progression system from heroes — they provide passive support rather than occupying a team slot. So Nezuko isn't competing with your existing lineup for a position; she's an addition to a different layer of your account.

That also means her value is evaluated differently. A Legendary pet's worth depends on what its effects do for your team composition, not on where it ranks against other heroes.

Her acquisition method hasn't been announced either.

Why Infinity Castle

The collaboration is specifically themed around Demon Slayer: Kimetsu no Yaiba The Movie: Infinity Castle Chapter 1 rather than the series as a whole.

That's a deliberate tie-in to current material rather than a general licensing deal, and it explains the roster. Tanjiro, Zenitsu, Shinobu and Giyu are the Demon Slayer Corps members at the centre of the Infinity Castle arc — the point where the series' final confrontation begins.

For players who don't follow Demon Slayer, the practical summary is that these four are among the franchise's most prominent characters, and a collaboration built on the current film is likely to carry more production effort than a back-catalogue crossover.

What isn't announced

• End dates for either wave, and whether wave one closes when wave two opens.
• How Tanjiro is obtained free — the specific event or campaign.
• How the Nezuko pet is acquired.
• Banner structure for Zenitsu, Shinobu and Giyu, including rates and pity.
• Whether the four heroes return in a future rerun.
• Collaboration story content, events and reward tracks beyond the heroes themselves.

That last point about reruns matters for anyone considering a skip. Collaboration units in most games return unpredictably, and licensed crossovers depend on the licence still being active. Nothing published says either way.

What to do before 1 October

Bank your rubies and summon tickets. Two waves two weeks apart means the wrong spending pattern costs you a hero.

Pick your priority among the four. Tanjiro is free; the decision is really between Zenitsu, Shinobu and Giyu.

Treat 1 October as a deadline for wave one, not a starting point. Precedent suggests short windows.

Check the free Tanjiro route before spending anything on the 1 October banners.

Watch for the end-date announcement. It's the single most important detail still missing, and it determines whether you can treat this as one six-week event or two separate two-week ones.

Building the roster behind them

Seven Knights Re:BIRTH values an account on its hero collection and the resources behind it — rubies, summon tickets, transcendence progress and pet development, all of which take far longer to build than a collaboration window lasts. Browse verified Seven Knights Re:BIRTH accounts if you'd rather enter the collaboration with a developed roster and currency already banked, and check the server, hero lineup and ruby balance stated in each listing before ordering — every purchase is covered by Buyer Protection until you confirm the handover.

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