Hollow Knight has somehow made its way onto a real PS1

Hollow Knight on a PlayStation 1 sounds like one of those projects built mainly for a convincing video clip. Lower the resolution, add some wobbling polygons, rough up the audio and you’ve got something suitably 1997. This project takes a very different route. Hollow Knight is being rebuilt to run directly on Sony’s original PlayStation hardware. No modern PC is hiding underneath, and this isn’t the standard game wearing a PS1 visual filter. The current build runs on a real console and already includes several recognisable parts of Hallownest. King’s Pass is present. So are Dirtmouth and the Forgotten Crossroads. Enemies roam around, Geo can be collected, masks work, walls can be broken and secret areas can be found. Progress can even be saved to an original PlayStation memory card. It’s nowhere near a finished version of Hollow Knight yet. Still, there’s enough running here to show how serious the project has become.

Hollow Knight has to fit inside a very small machine

The tricky bit isn’t making Hollow Knight resemble a PlayStation game. It’s getting its systems and assets running within hardware from 1994. Sony’s first PlayStation uses a 33.8688 MHz 32-bit RISC processor and comes with 2 MB of main RAM. Modern developers barely need to think about memory budgets on such a tiny scale. Here, every room, sprite, animation, sound effect and piece of game logic has to compete for a very limited amount of space.

The original PC release can’t simply be squeezed onto the console. Assets need converting into formats the PlayStation can handle, and game data has to be arranged around how the machine reads, stores and draws information.

Rooms, sprites, text and audio are converted for the old hardware, with dedicated code handling the game itself. Data can be streamed as needed rather than expecting the console to keep large chunks of Hallownest sitting in memory. It’s less a visual demake and closer to rebuilding Hollow Knight for another platform from the ground up.

PSoXide is doing much of the heavy lifting

Development uses PSoXide, a PlayStation development environment built around Rust tooling and aimed at software running on original hardware. The toolset covers graphics, audio, controller input, memory cards, asset conversion and disc creation. It includes an emulator too, giving the developer somewhere to test and profile code before checking the same build on a physical console.

Accuracy matters here. A game can run perfectly well in an emulator yet expose timing or performance problems once transferred to old hardware. Hollow Knight puts plenty of pressure on a system created decades before Team Cherry released the game, so testing on the console itself is a major part of proving the port works as intended. The current project remains an early slice. Large parts of the original game haven’t been converted, and there’s plenty of work left across mechanics, content and performance.

Hollow Knight remains a demanding 2D game

Team Cherry released Hollow Knight for PC in February 2017. The Australian studio’s 2D action adventure sends the Knight through Hallownest, an underground kingdom filled with interconnected areas, enemies, bosses and settlements.

Exploration sits at the centre of the game. New movement abilities open routes previously inaccessible, combat grows more demanding as progress continues, and its map gradually links into one large network of paths and shortcuts.

Hollow Knight became one of the most recognised modern Metroidvania games, helped by its hand-drawn artwork, precise combat and huge selection of locations. None of those traits make a PS1 conversion easy.

Being 2D doesn’t automatically make a game light on hardware. Hollow Knight uses large animated characters, detailed environments, layered scenes, numerous enemy types, audio and frequent transitions between rooms. Its original production targets machines with resources far beyond anything available in Sony’s first console. Every part needs reworking around older limits.

It’s already more than a technical demo

There’s no complete PS1 edition of Hollow Knight here yet, and this isn’t an official Team Cherry release. The project remains an independent port in development. Still, its current state goes beyond displaying a character inside a single test room.

You can move through multiple areas. Enemies function. Geo works. Secrets are present. Progress can be stored on a physical memory card. Those pieces turn the project into something much closer to an early game build than a short hardware experiment.

The bigger test comes next. Hollow Knight is enormous compared with the small opening section currently running on the console. Hallownest contains many regions, enemy types, bosses, abilities and interconnected systems, each creating another set of technical problems for PlayStation hardware. For now, a real PS1 can boot Hollow Knight, load part of Hallownest and let you play it. For a console launched more than 30 years ago, that’s already quite a technical exercise.