Pleaselog inorregisterto add a comment.
In Generation V, there is a chance of a critical capture, where the Poké Ball will only shake on the ground once, thus providing a higher catch ratio. When a critical capture occurs, the Poké Ball will pause in mid-air, shudder, and make a metal noise. Critical captures occur about as often as Critical hits, making them quite rare; however, even with such a small chance of occurring, a critical capture still presents a massive boost to the overall chance of capture for Pokémon with a catch rate of 3, who may have odds as low as .4%.However, a critical capture is not a guaranteed catch. It is possible for critical captures to fail, especially with Pokémon of lower catch
Its Called Crtitical capture and it hapens 1 out of 16 times when you throw a pokeball (less chance on legendarys, etc)
So, the pokeball shakes in the air, and then it will need just 1 shake (instead of 3) untill capture
So thats pretty much all LOL\
Calafox