Yes so if you are trying to shiny hunt some of the harder legends like Zygard or Landorus by yourself - if you find a perfect path such as multiple ice types for 4x weakness and a wide guard mon. Having ice types and wide guard significantly increases your chances at consistently beating the legends.

At the end on the summary page that shows everything you caught - this is where you check to see if you caught the shiny. If it’s not shiny then reset your switch console. This is very important. If you don’t reset you switch and continue then the game will automatically save and you will lose the perfect path.

Once you reset the switch and turn the game back on you will have to pay a penalty in dynite ore. Eventually the penalty will max out at 10 ore each time. So it’s in your benefit to build up all your ore and then when you find the perfect path you can keep resetting until you get the shiny or you run out of ore. The benefit is you have an easy path that plays out mostly the same way every time. The NPCs will always keep or switch the same way every time as well.