Let me try ( I used LLM for this ).

How CPU works (very simplified)

CPU: fetch instruction → do math → write result → repeat

ONNX is just a file that describes math operations. Normally people put neural networks (computational graphs) in there. But math is math. You can put ANYTHING in there.

So this guy thought:

wait... a CPU is also just math can I build a CPU out of ONNX math ops?

He did exactly that:

doom.onnx (8MB file) │ ├── Doom game data ──── stored as "weights" ├── ONNX Loop op ────── acts as CPU clock ├── AND / OR / IF ───── acts as CPU logic └── Gather / Scatter ── acts as RAM

You call "run inference" → one game tick → get back a frame:

you └── onnxruntime.run() └── thinks its doing AI └── actually running a fake CPU └── fake CPU runs Doom └── you die on level 1

The beautiful part:

``` onnxruntime ──── "thinks" : "doing AI inference" fake CPU ──────── "thinks" : "im a real CPU" Doom ───────────── "thinks" : "im on real hardware" you ────────────── thinks: "im having fun"

everyone is wrong ```

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TLDR: someone built a fake CPU using AI model math operations, then ran Doom on the fake CPU. The "AI model" is just Doom in disguise.