Toxicroak first appeared in Veilstone City when Team Galactic attempted to steal a bunch of meteorites. Toxicroak instantly formed a fierce rivalry with Brock's Croagunk. The two of them were at each others throats from the moment they saw each other and their rivalry seemed to go beyond the fact that they were on opposite sides. Croagunk even went so far as to ignore Brock's advances on women whenever it sensed that Toxicroak was around and their rivalry intensified when Toxicroak almost killed Croagunk by smashing him through a skylight and then stabbing him in the stomach with Poison Jab.
Toxicroak was often seen by Saturn's side and was present in almost all of his appearances, showing great loyalty to its master despite Saturn's evil intentions. It was able to defeat Gary's Umbreon and Electivire at the same time, an incredible feat considering that Gary used to be one of the most powerful trainers of his generation and Umbreon and Electivire were two of his strongest Pokemon. During its final confrontation with Croagunk, its pre-evolution finally managed to defeat Toxicroak with a devastating Brick Break, ending their rivalry. It is unknown what happened to Toxicroak after Team Galactic was defeated.
+ indicates this Pokémon used this move recently.* - indicates this Pokémon normally can't use this move.
Some Pokemon fans have wondered if Saturn's Toxicroak might be a Shiny Pokemon since it is a slightly different colour from ordinary Toxicroak in the games. However no mention has been made of Toxicroak's colour and it is generally considered to not be a Shiny Pokemon although a Shiny Toxicroak in the games is a lighter shade of blue, much like Saturn's Toxicroak.