Kernel Hearts Cast Guide: Confirmed Characters, Magical Girls, and Fortnite Crossover

Kernel Hearts is shaping up to be one of the most anticipated co-op action RPGs of 2026, and much of that early buzz comes down to its characters. The Kernel Hearts cast centers on four magical girls fighting to save a world drowning in ashes, but the roster runs deeper than the main squad — including a confirmed Fortnite crossover character and at least one mystery figure teased on the official Steam page. If you're wondering who you'll be playing as, who you'll fight alongside, and who's already been revealed, this guide breaks down every confirmed and reported member of the Kernel Hearts cast ahead of the September 17, 2026 launch.

The M.A.H.O.U Unit: The Four Magical Girls at the Core of the Cast

The playable heart of the Kernel Hearts cast is the M.A.H.O.U Unit, a squad of four magical girls tasked with climbing the Tower of Babel, eliminating the angelic creatures guarding each floor, and ultimately dethroning God. That lofty premise comes straight from the game's official description, and it frames everything the cast is built around: teamwork, transformation, and a fight against impossible odds.

Here's what has been officially confirmed about the four playable protagonists:

• They are explicitly described as four magical girls, making them the core of the Kernel Hearts roster.
• The game supports online co-op for up to four players, which means each player typically controls one member of the unit.
• Each character can activate a transformation that dispels the "Heavenly Curse," unleashing a devastating area attack and briefly unlocking their true form.
• Between runs, you return to a laboratory backup on the outskirts of Babel, where you can spend rewards and tweak your loadout.

The customization system is one of the most distinctive things about this cast. After each expedition, you can equip up to 256KB of chips onto your Unit's MAHOU.OS, effectively modularizing each character's abilities. That means two players can run the same magical girl with completely different builds, which adds real replay value to the Kernel Hearts cast.

It's worth noting that, as of now, the four playable characters haven't been fully named in the official materials we've reviewed. The official Kernel Hearts website includes a "Meet Your Squad" section, and IGN lists an "Official Meet the Characters" trailer, so detailed profiles are clearly on the way — but confirmed names for all four girls are still limited to what the developer has teased directly.

Confirmed Characters So Far: Fernet and the Dolce Announcement

While the four M.A.H.O.U girls form the structural core of the Kernel Hearts cast, two named characters have emerged from official sources ahead of launch.

Fernet

Fernet is the breakout star of the Kernel Hearts marketing push so far, thanks to a cross-promotion with Fortnite. The official Epic Games Store promotion reads: "Buy Kernel Hearts on Epic Games Store and get the Fernit Outfit in Fortnite as a gift with purchase." Note that spelling varies across materials — most coverage, including community videos, calls her Fernet, while one on-screen promo caption spells it "Furnit."

The skin is classified as a "Gaming Legend" skin in Fortnite, and community reports describe her as a visually striking anime-style character who looks great in the lobby and during emotes. One player video rates her eight out of ten, calling her a likely new main skin. That account is first-hand player experience rather than official marketing, but it lines up with how prominently Epic and the Kernel Hearts team are promoting her.

Dolce

The Steam page also features a banner that reads "⭐VERY IMPORTANT DOLCE ANNOUNCEMENT ⭐," which strongly implies a character named Dolce is part of the Kernel Hearts cast. At this point, official details on Dolce are scarce — we don't yet know whether she's a playable magical girl, an NPC ally, or something more mysterious.

The takeaway? The confirmed side of the Kernel Hearts cast is still small, but the pieces are starting to fall into place. Fernet is the one with a full public reveal; Dolce is clearly being positioned as a significant announcement; and the four M.A.H.O.U girls are the foundation everything else builds on.

The Supporting Cast: Allies and NPCs in the City of Babel

A roguelike lives or dies by its hub world, and Kernel Hearts seems to understand that. Between expeditions, players return to the city of Babel, described on the official website as a "cosmopolitan refuge" for humanity's last survivors. The official site highlights "a diverse cast of NPCs" you can socialize with and get to know before heading back to the tower.

This is where the Kernel Hearts cast expands beyond the playable squad. The game's Steam page lists a "Bond with Your Allies" feature that encourages you to interact with the tower's unique inhabitants and give them gifts to deepen your relationships. In practical terms, that suggests the NPCs in Babel aren't just quest dispensers — they're meant to be characters you actually care about between runs.

This hub-plus-cast structure gives the game an emotional anchor. In most roguelikes, runs blur together and characters feel disposable; Kernel Hearts seems designed to make the opposite true. The combination of a fixed cast (four magical girls) and a rotating space (the shifting tower) suggests developer Ephemera Games wants players to care about the people they're fighting for.

How the Kernel Hearts Cast Connects to Fortnite: The Fernet Skin Guide

The biggest real-world presence the Kernel Hearts cast has so far comes through the Fortnite crossover. If you want Fernet added to your locker, the process is straightforward but has a few important caveats.

The promotion works as a gift-with-purchase: buy or pre-purchase Kernel Hearts on the Epic Games Store, and the Fernet outfit shows up in Fortnite on the linked account. Community coverage of the process notes that you'll need access to a PC — you can't complete the purchase through an iPhone or iPad. You also need to be signed into the Epic Games Launcher with the exact same account you use for Fortnite, or the reward will land on the wrong profile.

One player report highlighted that the reward appears as a special in-game message the next time you log into Fortnite, confirming that the purchase and the skin are linked automatically. The same video showed Fernet in the lobby and locker with several emotes, which is worth reviewing if you're on the fence about whether the design fits your taste. Since the base game itself is a four-player co-op roguelike, the crossover is a smart way for Epic to put the entire Kernel Hearts cast in front of millions of Fortnite players before launch day