Kernel Hearts Classes Guide: M.A.H.O.U Unit Builds, Chips, and Magical Girl Combat

Kernel Hearts is shaping up to be one of the most anticipated co-op action RPGs of the fall, and the question players keep asking is how Kernel Hearts classes actually work. With release locked for September 17, 2026, on Steam and the Epic Games Store, Ephemera Games’ multiplayer roguelike makes a bold promise: gather your allies, eliminate angels, transform into a magical girl, and slay god. But underneath that pitch sits a character-building system that defies traditional RPG expectations. Rather than picking one fixed job at creation, Kernel Hearts classes grow out of the M.A.H.O.U Unit’s roster of four magical girls, a chip-driven operating system called MAHOU.OS, and the unpredictable powers each run supplies. That combination makes every expedition feel like a fresh build-crafting puzzle.

What Are Kernel Hearts Classes?

At first glance, Kernel Hearts looks like a straightforward hack-and-slash action RPG. Its Steam tags include Action RPG, Hack and Slash, Roguelike, and Online Co-Op, which paints a picture of fast melee combat with permadeath-style stakes. But the developers have been careful to describe the game as “a unique blend of action RPG and roguelike elements with multiplayer co-op.” That roguelike DNA is exactly what reshapes the class system.

Instead of a traditional pick-a-class screen, your role inside the Tower of Babel is assembled from three layers:

• The squad member you choose — one of the four playable magical girls.
• The chips you install — up to 256KB of equipment on your Unit’s MAHOU.OS.
• The unique powers you collect — attacks, spells, and movement options that change every run.

In practice, your Kernel Hearts classes loadout is something you rebuild constantly rather than a permanent decision. The game rewards experimentation, and the official materials emphasize that mix-and-match philosophy at every level of combat.

The Four Magical Girls: Your Squad Is Your Class Foundation

Official materials describe Kernel Hearts as a game about “four magical girls and their attempt to save a world that’s drowning in ashes.” The official website’s “Meet Your Squad” section highlights the four playable members of the M.A.H.O.U Unit, and each one appears to bring a distinct combat identity to the team.

While Ephemera Games has not published formal class names for each girl as of this writing, the squad structure strongly suggests that your starting pick is the closest thing to a traditional class choice. Think of it this way: the girls are the base kits, and everything else — chips, per-run powers, transformations — is how you evolve that kit into a specialized build.

Until the full roster details go live, the smartest approach is to try each girl in the demo and note which playstyle feels natural — ranged pressure, melee aggression, mobility, or utility. That first impression will become the foundation of your preferred class strategy.

MAHOU.OS Chips: Building Your Class With a 256KB Budget

Here is where Kernel Hearts gets genuinely original. After every expedition, your Unit’s memory rolls back to its most recent backup in a laboratory on the outskirts of humanity’s last holdout. There, you spend the rewards from each run to unlock and equip up to 256KB of chips onto your MAHOU.OS, customizing your Unit as you see fit.

Think of the chip budget as a deck-building constraint for your stats and skills. Two players could pick the same magical girl but walk into the tower with completely different class identities — one built for sustained melee combos, the other for spell-heavy burst damage.

When you are spending rewards, keep these tips in mind:

• Pick one primary synergy first. Doubling down on a single combo style is often stronger than spreading chips thin.
• Respect the movement budget. A class that cannot reposition will struggle against the tower’s shifting layouts.
• Use the demo to test chip feels. The free demo available on the Steam page is a low-risk way to learn what each chip type does before launch.
• Treat the 256KB cap as a design feature. The limit exists to force meaningful tradeoffs.

Roguelike Runs: How Your Class Evolves Mid-Climb

The roguelike structure means your class is never truly finished. Each expedition into the Tower of Babel is a fresh improvisation. The Steam page promises that you can “mix and match your attacks, spells, and movement with unique powers during each run to unleash devastating combos on the enemies you encounter.”

That sentence is the key to understanding Kernel Hearts classes in practice. You enter a run with a chip-defined class shell, and then the run itself hands you new tools that reshape how that class plays by the final floor.

The boss fights deserve special attention. Every level culminates in an intense fight against the floor’s guardian, and those fights are where the quality of your class-building decisions becomes obvious. If your movement is too stiff or your damage is too spread out, the guardian will expose it quickly.

Co-Op Team Composition: Building a Balanced Squad

Kernel Hearts supports online co-op for up to four players, and the Steam description sums up the fantasy perfectly: “Punch biblical monsters in the face with up to four friends.” A good class build matters even more in multiplayer, because your team needs to cover multiple roles at once.

A few communication rules will make any composition stronger:

• Call out the domain guardian. The player with the best burst class should confirm when their transformation is ready.
• Save transformations for adds. The area-of-effect on the transformation can clear a cluttered boss room instead of going into a single target.
• Coordinate chip economy. In co-op, you can complement each other’s weak spots instead of duplicating strengths.
• Keep one movement skill available. Someone on the team always needs to kite enemies away from downed players.

Transformation and Bonds: Combat Power Beyond Your Class

The transformation mechanic gives Kernel Hearts a distinctly magical-girl combat identity. Harnessing the strength of the tower dispels the Heavenly Curse from your body, unleashes a devastating attack on nearby foes, and grants you your true form for a short period. Regardless of your Kernel Hearts classes build, transformation is a universal equalizer — a burst of power that rewards smart timing.

Outside of combat, bonding adds another progression layer. Back in the city of B