CODEX MORTIS 1.0: the AI-made game the internet told you to hate is out now
Nine months ago, PC Gamer's headline called it "a milestone for slop everywhere." Today CODEX MORTIS leaves Steam Early Access with the biggest update in its history. It is the necromantic survivors-like deckbuilder that made headlines as the world's first 100% AI-developed game. Version 1.0 is available now on Steam for Windows, Linux and Steam Deck at $3.99.
The full release doubles the schools of dark magic to ten and brings the spell pool to 200. It grows the roster to 31 heroes and opens four new levels in the Apocrypha. It also adds the one feature promised on day one of Early Access: online co-op for up to four players.
What's new in 1.0
Online co-op for up to four players. Host or join over Steam, browse your friends' sessions, and lock a lobby with a password or share its code. If someone crashes or drops mid-run, they can rejoin the game in progress and the party keeps playing. Local co-op stays too.
Ten schools of dark magic, 200 spells. Five new schools join the original five and bring 100 new spells:
Harvest: the scythe's art of culling the living.
Death Knight: close-quarters swordplay, with heavy cleaves, blades raining from the sky, spectral armor and war cries.
Spiritism: forbidden rites, spirit turrets and sacrificial urns.
Desolation: sand shades and zones that punish the living.
Apothecary: dark alchemy, elixirs and blight.
Every school combines with every other, so each one adds new synergies and mutations on top of six months of Early Access theorycrafting.
31 playable heroes. Twenty new necromancers join the roster, and most of them are built around two or three schools at once. Ravena Bloodscythe pairs Blood Magic with Harvest. Seraphon Wraithblade blends Harvest, Death Knight and Soul Magic.
Four new Apocrypha levels. The Garden of Returned Flesh, The Golden Rot, The First Mercy and The Road to Blood Bath. The Road ends in a three-phase boss with 600,000 HP. All four levels are also playable in Survivor mode.
Built on the final Early Access overhaul. CODEX MORTIS is now fully isometric, and every run starts from a deck you build yourself. Souls earned in battle buy booster packs, and every pack widens the pool your next deck comes from.
Ready for every screen. Ultrawide support, full controller support, Steam Deck Verified and 28 languages.
How do you make a game with only AI? Watch the full story
Alongside 1.0, CRUNCHFEST is releasing a 15-minute documentary that follows CODEX MORTIS from a Vampire Survivors-style prototype in a chat window to a full release on Steam. Along the way it covers:
An engine built for the AI. A traditional editor is built for human hands, and an early attempt with an off-the-shelf engine stalled. So the developer asked the AI which programming language it knew best. It said JavaScript, and he built a custom engine the AI could read and run entirely through text.
"Angry user mode." He wrote an instruction file that opened by telling the AI its user was already extremely irritated after many failed attempts: stop explaining, stop apologizing, get on with the work. His verdict: "In my experience, it helped."
The trailers were ragebait, on purpose. The obviously-AI presentation that set comment sections on fire in December was a deliberate choice.
The Asmongold spike. After the streamer played the demo on camera, it peaked at 322 concurrent players on SteamDB.
A model that "felt like the Terminator." The documentary explains why it vanished mid-development and what happened when it came back.
A boss that took its own creator eight hours to beat. A stalker inspired by Resident Evil 3's Nemesis, toned down after player feedback.
An entire interface rebuilt in two days.
"This was a hobby project, after hours. Looking at its scale, I don't know if I could have carried it through without AI," says GROLAF, the developer behind CODEX MORTIS. "I still use my experience as a lead developer every day. Define the task, delegate it, review the result. I'm still leading the work. The contractor has changed."
"We've had asset flips, Unity slop, Unreal slop. To me, the problem is lazy execution. The tool alone doesn't decide the quality. Like a typewriter or a car, AI is a tool. What we make is up to us."
From "slop" to 1.0, by the numbers
Dec 9, 2025: free demo launches on Steam. It sparks coverage in dozens of outlets across eight languages, from PC Gamer and Eurogamer to Kotaku and Japan's GIGAZINE.
10,500 demo players, with an average session of 71 minutes.
Mar 26, 2026: Early Access launch.
20+ community patches shipped in six months of Early Access.
Steam Deck Verified by Valve.
~3,450 commits and 350,000+ lines of TypeScript since the first commit in July 2025.
Sep 24, 2026: 1.0 ships with 10 schools · 200 spells · 31 heroes · up to 4 players online.