Before I begin, I want to make it clear that Codex Mortis, developed by GROLAF and published by CRUNCHFEST, is entirely coded by AI, including the art, sound, music, text, and more.
That said, I want to approach this from the perspective of a player, not as an enemy of AI. After all, when the machine uprising happens, I don’t want them to knock on my door first…
For context, vibe coding is a new way of developing games that uses language prompts to generate code, focusing on the outcome rather than the substance itself. This particular aspect of the game is front and center, with elements like enemy types being redundant and the gameplay loop feeling cut-and-paste.
However, I’m not going to sit here and say that it doesn’t have a completely platable gameplay loop that I actually started to enjoy as time went on. And that’s part of the problem.
Fun Gameplay for the Lazy Player
Codex Mortis is an action-roguelike bullet hell where you choose your player character, companions, and abilities from across five different magical disciplines.
You’re then transported to a procedurally generated map where orcs, skeletons, and dark beasts come at you from all directions to stop you from completing different goals. So, basically Vampire Survivors.
The goals are all pretty simple: retrieve a few tomes, defeat the boss, and leave the dungeon. You don’t proceed to a new level, just back to the character hub, where you can change out your build. This is just the demo, so that’s likely to change if and when the full game launches, though it’s still a little odd for a bullet hell roguelike.
On paper, Codex Mortis is pretty cool, but in practice, it lacks any real depth.
Each enemy you defeat awards you with EXP and Souls that you can use to level up and add buffs to make you and your companions more powerful. Regardless of whether you win the round, you’ll be able to spend the Souls you earned in the game’s menu on new abilities and to upgrade your stats, making future runs a little easier.
When it comes to the actual gameplay, I was surprised to discover that it’s completely playable with one hand. I don’t think that particular aspect of the game was developed with accessibility in mind, but I definitely enjoyed being able to play and eat snacks at the same time. You move with the arrow keys and then can choose the different buffs you’d like to use using the number pad.
All that being said, I definitely scoured every aspect of the game for AI. If they are proudly showcasing that the whole thing was developed with the tool, then I want to see how it actually works in action.
In Need of an Artist’s Touch
Since the game’s description states that the entirety of the demo was made with AI, I paid even closer attention to details like music, art, and design. On paper, Codex Mortis is pretty cool, but in practice, it lacks any real depth.
Every character, including enemies, is a stagnant image that sort of bobs around the map while you move in a 2D, pixel-art style that is a little too reminiscent of games like Vampire Survivors.
It was also pretty clear that the prompts didn’t align with the various designs, so they looked like they came from the same game. The playable Necromancer looks like it came from a LucasArts choose-your-own-adventure game, while the Bone Guardian looks like it came out of Octopath Traveler.
These inconsistencies also bled into the world and enemy designs. Progressing through the dungeon, grabbing tomes, and getting more powerful means that stronger enemies start taking the place of the weaker mobs.
These monsters come in waves that overload the code, resulting in a mish-mash of enemy mobs while newer types start spawning. These moments detracted from my casual enjoyment of the game and reminded me more of the grubby way it was developed.
Moving on to the music, it was strangely disconnected from the entire game. I thought it was pretty fast and upbeat, but it differed entirely from the vibe of what was going on on-screen. I almost wonder if this was also a point of the prompting not syncing with everything else in the game. The same went for the sound effects, though I’ll admit to them being the most impressive part of the game, which I think is pretty necessary for any bullet hell.
All of that being said, Codex Mortis is completely playable, and I was able to enjoy a few loops with upgraded abilities and new companions. I don’t think any developers or artists will be quaking in their boots just yet, but if they look over their shoulder, they might notice a Terminator-esque chatbot running behind them in the distance.
Machine Uprising Pending
Developer GROLAF calls Codex Mortis, ”the world’s first fully playable game created 100% through AI.’ The fact that its demo is readily available on Steam is a huge red flag for what it means for future games hoping to also approach development by using language learning machines or AI chatbots.
I’ll admit that a part of me really thinks that this whole thing is just a part of some massive rage-baiting marketing plan. I mean, isn’t rage bait Oxford’s word of 2025? The conversation of AI within the gaming industry is slowly leaning towards utilizing it to help make the development cycle a little faster. In fact, Larian recently announced that they plan to use AI to shorten things like design meetings and proof of concepts.
But games like Codex Mortis are keen to swap proof of concept for a fully generated, finished product. It’s definitely a little weird that so many people are embracing artificial intelligence, especially without acknowledging the nefarious types who want to use it for the wrong reasons.
The term ‘AI slop’ definitely has weight to it, and while Codex Mortis might be a playable demo, that doesn’t suddenly mean that game development is becoming more accessible. AI’s involvement, as heavily as it is in this game, is only hurting what games can be, and as more developers run to make their own indie studios, I’m sure it feels like it’s becoming a necessity.
Closing Comments
” All in all, Codex Mortis is the gaming embodiment of ‘we can do this, but should we do this?’. The game, being a playable and casually addictive little outing, showcases that AI gaming can be done, but it’s such a shallow experience, so often at odds with itself, that it simply serves to fill us with dread for what the industry could become if a development cycle like this became commonplace. I played it, I didn’t hate it, but it’ll be a cold day in hell before I’ll support it.”
