Why does your Ultra Ball fail three times in a row on a Pokémon with 1 HP? Because catching follows a precise formula, where every element counts: the species, the remaining HP, the status and the Ball. Understanding it means no more wasted Balls, and catching legendary Pokémon much faster.
This file explains the fourth-generation catch formula, compares the real effectiveness of each Ball in Sinnoh and gives worked examples for the most common cases.
Good news: Diamond, Pearl and Platinum add several Balls that are very effective in specific situations, such as the Dusk Ball, the Quick Ball and the Timer Ball.
