I will also say time travel but in case you worry about the consequences, there really aren’t any except for turnips rotting and losing progress for nook miles at the Resident services ADB machine. Otherwise it’s the best way along with treasure islands of quickly getting your island back to some semblance of where you were before. And if treasure islands are your thing, I also highly recommend getting a month subscription to one of the channels on tiktok or youtube so you can go to their sub-only islands that get MUCH less traffic. It can take hours to get stuff with people coming and going on regular treasure islands.