Reversing Factorio's RNG

Discussion (5 Comments)Read Original on HackerNews

strstr•35 minutes ago

I did an easier version of this in my college intro class. There was a class competition that involved rock paper scissors as a subcomponent, and ties were broken with randomness. You could rig Java’s prng so you would win all ties.

The prng was seeded with usec time at first call. I called the rng a bunch of times to harvest entropy, and scanned the plausible usec times to find the seed. Then I primed the prng so I would win ties.

Frankly, I assume I implemented this wrong, but the theory was there lol.

rogueaine•10 minutes ago

That’s not at all what the article proposed. The author constructed and transpose to the linear shift register coefficients and built a circuit network based on this to predict the next state (in the sandbox) and direct recipes.

pema99•4 days ago

Super cool

jvanderbot•about 1 hour ago

Yeah, no notes. It's remarkable.

TL;DR: Wired up an in-game predictor of RNG output and used it to only craft legendary items when RNG would line up to roll legendary.

From base to legendary at a suprisingly high rate. Look very closely at the video at the top of the post - what I was seeing didn't sink in until I had finished the article. Amazing.

lowbloodsugar•about 1 hour ago

Madman. Brilliant.

Reversing Factorio's RNG

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Discussion (5 Comments)Read Original on HackerNews