An interesting glitch in Hyrule Warriors allows you to not just win more rupees than normal: it makes your wallet full of them, giving you a total of 9,999,999 rupees. It is the fastest way to win money in the game.
Basically, you need to beat a giant boss (so far, it is confirmed for Gohma, King Dodongo and Argorok) without using weak attacks, where the only requirement needed is to have \’Rupees+\’ on your weapon. It doesn\’t matter what rank your weapon is nor the character and level you are using. Still, it’s recommended to have full Stamina Fruit Badges in order to reduce the Weak Point Gauge. Also using Lana’s Summoning Gate makes the progress even easier; still, if you accidentally trigger a weak point attack, it can be easily fixed by just using the restart level feature.
You can see the glitch on action below, and find more details in this Reddit thread: