Serebii already existed back in gen 3, including an IV calculator on the site. Sure, you had to stockpile Rare Candies, save, then level up your hatchlings to like level 30 and recording the stats at every level along the way to get accurate calculations, and then soft-reset to get your Rare Candies back, but it was possible. How did they breed them? Just lots and lots of patience to get a couple of IVs right, I spent dozens of hours breeding a single pokémon to get as good IVs as I could, I still have a Salamence in Emerald with 2 perfect IVs in Speed and Attack, and over 25 in all the defensive stats. You kept on testing everything you hatch through Serebii's IV calculator and continued to breed with the best ones you had, until eventually you just didn't get anything better any more and it wasn't feasible. 5 perfect IVs was something that was reserved for hackers, that was simply impossible to do legitimately.how were competitive pokemon bred in gen4 online battles back in the day without any sort of RNG manipulation? there is no IV rater so you can only guarantee 1 perfect IV and any other are hard to determine without a IV calculator. getting perfect 5IV pkmn is much easier after an IV rater is available.