So here's a story of, by far, the weirdest bug I've encountered in my CS career.
Along with @maciejwolczyk we’ve been training a neural network that learns how to play NetHack, an old roguelike game, that looks like in the screenshot. Recently, something unexpected happened.
![](https://kbin.life/media/cache/resolve/entry_thumb/d1/bc/d1bcc0371466fd73fa1834996e82b31182beaaf6fd632f1394329dfc38dc5dc3.jpg)