After Elden Ring on N64, FFX on PS1 !

Ever polled your memory for the massive leap from the original PlayStation to the PS2? When Final Fantasy X dropped in 2001, it blew minds with its fully 3D environments, expressive faces, and voice acting. It felt like the future. But indie developer and YouTuber 2009aero recently asked a fascinatingly unhinged question: What if Square had tried to make FFX on the original PS1 instead?

Not as a PC remake. Not as a fancy modern engine with a "retro shader." We are talking about real, homebrew code running on actual, 33MHz 1994 PlayStation hardware.

The result? A brilliant, glitchy, and deeply impressive tech demo that reminds us just how much smoke and mirrors went into making '90s video games work.

The Ultimate Stress Test: Macalania Temple

Instead of starting small, the developer decided to recreate one of the most mechanically demanding sequences in the game: the dramatic confrontation and boss fight against Seymour Guado at Macalania Temple.

"A room can look fine in a still image, but it doesn't become a game until someone can move through it."

At first, blocking out the temple in full 3D completely broke the PS1. The live-textured models caused massive frame drops. To fix this, 2009aero had to resort to the exact same trick Square used for Final Fantasy VII, VIII, and IX: pre-rendered backgrounds.

By taking a snapshot of the 3D room, converting it into flat PS1 "TIM" texture strips, and mapping the camera angle, the console stopped rendering the actual temple structure. Instead, it just drew a flat image and slapped the real-time character models on top.

Cracking the Disc-Streaming Video Code (FMVs)

You can't have a PlayStation-era Final Fantasy without full-motion video (FMV) cutscenes. To get Seymour’s dramatic grand entrance into the game, the creator animated a short, beautifully retro '90s CG-style clip in Blender.

Getting it onto a PS1 disc, however, required converting it into an .STR file, which is a disk-streaming format specifically designed for the PS1's dedicated hardware decoder (MDEC). At 1.3 megabytes for 58 frames, the console actively streams the video sectors straight from the disc into VRAM in 16-pixel-wide vertical slices while the game is running.

Saving 128 Kilobytes to Prevent Total Meltdown

Building the battle sequence brought its own set of nightmares. At one point, the developer added a "Guad Guard" healer model, and the entire game simply refused to boot. This wasn't a visual glitch; it was a total exhaustion of the PS1's tiny 2MB of system RAM.

The fix? Some unglamorous, hardcore memory optimization. By trimming down a dual frame buffer called the Packet Arena (where the CPU preps polygon draw commands) from 262KB to 196KB, they saved exactly 64KB per buffer. That freed up 128KB of RAM globally, taking the project from a fatal 57KB of free headroom to a stable 185KB.

On a modern PC, 128 kilobytes is literally nothing. On a PS1? It’s the difference between a working video game and a bricked console.

Fighting the Frame Rate: From 7 to 20 FPS

Even after getting the battle to boot, it initially ran at a painful, slideshow-like 7 FPS.

To make it playable, 2009aero implemented classic dev shortcuts:

• Culling: Anything off-screen or irrelevant to the shot stops drawing entirely.

• Mesh Caching: For static animations, the game projects the 3D mesh into 2D screen space once and replays those calculated triangles instead of calculating them every single frame.

• The "Void" Trick: For massive attacks, like summoning the Aeon Shiva (a heavy 2,100-vertex model imported from the Final Fantasy III DS port), the game cuts the background entirely to display a black void. Without an environment to render, the PS1 can afford to process heavier spell effects like Watera.

With these optimizations, the frame rate jumped up to a cinematic 19–20 FPS. As the creator jokes, after suffering through 7 FPS, 20 frames felt like playing on a "240Hz 4K monitor."

Pure Nostalgia on a Real CRT

The attention to detail here is brilliant. The UI uses the iconic yellow turn indicators, the classic Final Fantasy blue menu boxes, and the retro hand pointer. The author even included the infamous "Tidus Laughing Scene" as a custom FMV because, as they put it, "every Final Fantasy X project is legally required to include it."

Seeing the final footage running side-by-side on a modern monitor and a vintage CRT TV feels like peering into an alternate timeline.

Ultimately, this project highlights the sheer genius of '90s developers. Pushing these kinds of complex narratives and mechanics into hardware hundreds of thousands of times weaker than modern phones required magic-tier engineering. It also perfectly explains why Square wisely chose to wait for the PlayStation 2 before releasing the real Final Fantasy X to the world.

You can check out the full homebrew process and see Anima get summoned on real hardware over on the 2009aero YouTube Channel :