In Pokemon Ruby,Sapphire and Emerald after you make a pokeblock, you can check the pokeblock case and you give the desired Pokemon the pokeblock to help it do better in Pokemon contests. After you have received a pokeblock case and you made pokeblock at the berry blending machine go to your key items in your bag and scroll down to your pokeblock case then simply select the pokeblock you want to give your Pokemon.
Pokeblock's are not in diamond instead there called poffin's, just like ruby, sapphire and emerald in the Pokemon contests you can create your own poffin using berries.
First you must bet the PokeCase that carries PokeBlocks from someone in one of the Talent Show buildings. After that talk to an old man in the Talent Show building and he will ask you if you want to make a PokeBlock. Keep in mind that you have to have a Berry to make a PokeBlock!
Blue is the best one, But Indigo are the easiest to get.
Now you can't normally do this unless you go in the safari zone in ruby, sapphire and emerald and put a pokeblock in the pokeblock feeder. See here's the cool thing about the pokeblock feeder, the Pokemon that normally appear in that area will either go for the food or not go near it so chances of finding certain Pokemon actually increase so lets say you want to find wobuffet put a pokeblock that is either indigo or green chances of finding it now has increased!
you need to get the pokeblock case
You need to have the pokeblock case and just go inside P.S. you get the pokeblock case at the left receptionist In the lilycove contest hall
Do that game almost perfectly with friends or the pokeblock master.
This depends on the pokemon's nature, not the species.
it depends what game you have if you have sapphire you get it in staleport city talk to the little girl in the poke contest
If you are playing on emerald, you can interact with any of the tables the npcs are sitting at to make a pokeblock!
you have to thorw a pokeblock, the more the better, but be careful,,,they might run away