Pokémon Ruby Tips

How to get the Secret Pokemon: Shedinja
First, catch a Nincada. It can be found along route 116. Remember what type of ball you caught it with, and make sure you have at least one of it in your pack. Make sure you have only a maximum of five monsters in your party. (there must be at least one space in your party).

Train your Nincada until it reaches level 20, then it will now evolve into Ninjask. Now, it will learn a lot of new moves at this stage. And when you've finished, look at the ball packs.

The ball will be missing and you'll have a new Pokemon in your party called Shedinja. Shedinja has all the moves of your Ninjask, has only one HP and has an ability called "Wonder Guard".