Verified answer

When a pokemon spawns it has a number for each of its stats. That number is from 1-31. It affects how high that stat can be. It has nothing to do with nature, for it is an entirely separate entitity. Look up an iv calculator or go to the judge in the pokemon center in kilo use city. There are ways to breed ivs on to pokemon, but you need to look those up yourself. Hope I helped, I have played competitively for many years, and ranked high in several

Tournaments.