Ash's Totodile first appeared while Ash and Misty were fishing. Both tried to capture it with their Lure balls but it hid in the bushes and they didn't know which of their balls actually captured it.
Brock suggested that they should have a Pokémon Battle to determine who would get to keep it.
Ash Ketchum ended up winning the battle and got to claim Totodile. Right after
Ash Ketchum and
Misty had their battle, Team Rocket showed up and tried to steal their Pokémon. Totodile seems to like
Jessie's hair as he instantly went after it and bit a chunk off it which angered her. Team Rocket was no match for
Ash's Totodile as it quickly took care of them.
Ash's Totodile is very energetic and curious. It is always dancing and jumping around in any situation regardless of the conditions they are in. It's personality though seems to help lift other up that encounter it.
While trapped in a cave at the Hot Springs near Ecruteak City,
Ash's Totodile showed that it was a Pokemon of good character by saving
Meowth from a falling rock even though Meowth was trying to capture it.
Meowth was surprised by Totodile's regards for all living creatures but it showed that Totodile was raised well by
Ash Ketchum to have good morale regardless of the situation.
Alto Mare Summer Festa Race
Ash Ketchum selected his Totodile to race at the Alto Mare Summer Festa where water Pokémon pull their trainer down the canals of the city.
Ash's Totodile's main competitor was
Misty's Corsola who was neck and neck against it for a lot of the race. It made too fast of a sharp turn which knocked off
Ash Ketchum but Alto_Mare_Latias picked the two of them off and raced them towards the finish line. They quickly passed
Misty but Alto_Mare_Latios showed up and took all of them off course just before
Ash Ketchum was about to win.