Ship it everywhere.

In 2020, a group of speedrunners did something I keep thinking about as an engineer.

There’s a minigame in Zelda: The Wind Waker that looks purely random — 604,584 possible boards, and for years it wrecked otherwise-perfect runs. Then a team reverse-engineered the binary and found the truth: the game never rolls dice. It runs a deterministic generator seeded with the same three numbers every single time — (100, 100, 100). The “randomness” was just a sequence nobody had located themselves inside of.

That reframing scales up further than it has any right to.

If you wanted to “rewind” a closed system by storing its full state and writing it back, the bill is absurd — for our universe, on the order of 10⁹⁹ joules, because of Landauer’s principle and the holographic information bound. But there’s a second option the speedrunners stumbled onto: don’t store the state, store the seed and the rule, and regenerate. That’s not a rewind. It’s a re-run. And it costs almost nothing.

The engineering lesson underneath the physics: the true cost of a system isn’t the size of its state — it’s the length of the shortest program that reproduces it. Snapshot-and-restore is expensive. Deterministic replay from a seed is cheap. We rediscover this every time we choose event sourcing over giant state dumps.

I wrote the long version as an interactive essay — you can fire at the board, reveal the seed, and watch entropy refuse to loop.

Link in comments. 👇

Speedrunners cracked a “random” Zelda minigame by finding its fixed seed: (100,100,100). New essay: that same trick is the only affordable kind of time travel. Don’t store the universe & rewind it (10⁹⁹ J). Re-run it from the seed. Playable 👇

A “random” Zelda minigame had 604,584 boards and wrecked speedruns for years.

In 2020 runners found the truth: it was never random. Fixed seed, (100,100,100), 10M deterministic calls deep.

That trick is also the only version of time travel physics can afford. 🧵

Subtitle: A deterministic minigame, a fixed seed, and the cheapest version of the past the universe will actually sell you.

Before you import: Use Medium’s “Import a story” tool with the canonical URL so Medium credits the original and you don’t get dinged for duplicate content. Add this line under the title:

Originally published at jasonburt.page. This version is text-only — the interactive one (fire at the board, reveal the seed, watch entropy fail to loop) lives on the site.

Tags: Physics · Programming · Games · Science · Information Theory

Kicker / pull-quote to feature: “The board was never random.”

Then paste the full essay body. Open with the Sploosh Kaboom setup, land the “store-and-restore vs. re-seed” split, and close on the open question: is the universe rolling dice, or running a generator with a seed we can’t see?