It is as the title says. It’s been discovered that, in the original Animal Crossing on Gamecube, if you read the village Message Board 43 times, it’ll reset your axe’s durability. But there are more consequences than just that! It’s explained in HunterR’s 10-minute video.
So, why does this happen? The precise details are in the video, but here’s a summary.
When you’re holding an axe, the game is not discriminating about which A button presses cause it to degrade—or, rather, its damage value will increase. If you hit objects other than trees, it’ll pick up three times as many damage points. But you can do other things that use the A button, and if an axe is in hand, its also take on damage.
There are actually eight different axe objects, that are switched between when eight points of damage is taken. (The more damaged versions have slightly different appearances.) The damage counter isn’t actually tied to the axe: it’s a separate count that’s counts for all axes. (Meaning, if you have multiple axes and try to spread out the wear between them, technically only the axe that you’re holding when you take the eighth damage point really gets harmed.) The value is also not saved when you save the game; if you hit trees seven times with an axe, then save and reload, the wear will be forgotten.
If you do something with the A button while the axe is in hand, but it doesn’t strike an object that might cause it to break, it’ll keep gaining damage. If you’re facing an object that isn’t a tree, like the Message Board sign, it’ll even gain three as much. But the check that switches to the next-most-damaged axe type only happens when the axe actually hits something. (It also happens if you open doors with an axe in hand!)
The counter to check if the axe should take wear is a single byte interpreted as a signed value, so, if you can get it to 128 or higher, the high bit is set, so the C library code used for the game’s comparisons will consider it to be a negative number. 43 x 3 is 129, or -126. You can then keep using the axe over and over until the number turns positive again, at 0, or until you save the game and reset the counter anyway.
By the way, to bring this to the realm of things I have personal knowledge of… Animal Crossing New Horizons doesn’t have a similar bug (as far as I know at least), but there is a different unexpected aspect of its tool-breaking. If a timer is running, like from hitting a rock for Bells or from participating in a round of a fishing or bug-catching tournament, tools won’t break until the timer expires, even if they exceed their durability limit. It’ll count the damage, but it won’t actually break the tool until the timer runs out. If you don’t use the tool in a way that might cause it to break, then it won’t, not until you next use it. If you’ve kept track of how much wear it’s taken, you can then sell it at Nooks and get some of the value for it.
