Kernel Hearts is a multiplayer co-op roguelike action RPG from Buenos Aires studio Ephemera Games, published by Whitethorn Games. It launches in 2026 on PC via Steam and Epic Games Store, PlayStation, Xbox, and Nintendo Switch. A demo is available now on Steam and Epic Games Store.
The setup is blunt. The world is drowning in ashes, and the solution is to climb the Tower of Babel and dethrone God. Players control members of the M.A.H.O.U. Unit, a squad of magical girls tasked with fighting their way through angelic creatures floor by floor, boss by boss, run by run. It wears its anime influences openly, mixing biblical imagery with the kind of transformation sequences you'd find in a Saturday morning show, and the collision of those two things gives Kernel Hearts a tone that sits somewhere between reverent and absurd.
Combat leans on mixing attacks, spells, and movement abilities with powers that shift between runs. The roguelike structure means each attempt up the tower reshuffles what's available, pushing players to build combos from whatever the run hands them rather than settling into a single optimized loadout. Up to four players can fight together in co-op, and each floor ends with a boss fight against the domain's guardian. The transformation mechanic ties directly into combat too. Players can harness the tower's energy to dispel something called the Heavenly Curse, triggering a burst of damage to nearby enemies and temporarily shifting into a more powerful form. It functions as both a room-clearing tool and a momentary power spike, the kind of mechanic that gives a run its punctuation marks.
Between runs, the loop pulls back to a laboratory on the outskirts of humanity's last holdout, described as the last memory backup. Rewards earned during expeditions are spent here to unlock and equip chips onto a system called MAHOU.OS, with up to 256KB of chip capacity to customize each unit. The framing is deliberate. Everything about the M.A.H.O.U. Unit leans into the idea that these characters are as much machine as magical girl, and the chip system reinforces that by making progression feel like hardware upgrades rather than traditional leveling.
The tower itself isn't just a gauntlet. Unique inhabitants live within it, and players can interact with them and offer gifts to deepen bonds. It's a quieter thread running alongside the combat, giving the space between fights something beyond menu management. How deep those relationships go or what they unlock isn't clear from what's been shown so far, but their presence signals that Ephemera Games wants the tower to feel inhabited rather than purely hostile.
The mood holds everything together. A world reduced to ashes, angels as enemies rather than allies, a god that needs to be removed rather than worshipped. Kernel Hearts inverts the usual hierarchy and plays it straight enough that the stakes feel real, even when the characters are punching biblical monsters in the face while dressed in magical girl outfits. The tension between the grim premise and the bright, anime-inflected action is where the game seems to find its identity. The pacing of each run builds toward those guardian boss fights at the end of every floor, giving the climb a rhythm of escalation that resets with each new attempt from the lab.
Kernel Hearts is the kind of game that puts its contradictions right up front. Angels are the enemy, God is the final boss, and the heroes are magical girls running on upgradeable operating systems in a tower built from scripture. Whether that cocktail holds together over dozens of runs will come down to how well the combat systems reward improvisation and how much the tower changes between attempts. The demo on Steam offers a first look at exactly that.