You might need to obtain the Poffin Case in Pokémon Ruby, Sapphire and Emerald. You can find it at the Slateport PokeContest Hall.
you can only get pokeblocks in ruby, sapphire and emerald. However if you talk to the Pokemon fanclub chairman he'll give you a poffin case. And you can make poffins in the poffin house at hearthome city.
feed it a sour poffin, you can get a poffin case in the Pokemon fan club.then make poffins at the poffin house.
if you have a poffin case go to Harthome city and go into the house south of the Pokemon center talk to the lady by the pot and answer her questions. to get the poffin case go to the house to the right of there and talk to the guy he will give you the poffin case.
first go to hearthome city and go to the Pokemon fan club talk to the chairman and he will give you a poffin case =p
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.
Pokemon fan club
Where You Get The Poffin Case:-Original Answer- Enter the Pokemon Fan Club located next to the Poke Mart. Talk to the FanClub chairman and he'll give you the POFFIN CASE-Improved Answer-First, go to the Pokemon Fan Club. It is located in Hearthome City. There's a man standing in the club who is obviously the owner, due to his brown suit, brown hat, and white beard/hair. He is behind the big table, standing there facing the door. If you talk to him, he will give the Key Item, the Poffin Case, to you.The Poffin Case is for making Poffins, which can improve a Pokemon's performance in Shows.
Unfortunatley, there is no way to make a Mild poffin except for the one that the guy in the contest hall gives you when you first receive your poffin case. However, there is sililiar poffin called the Sharp poffin that is similiar to the mild poffin and is the same colour. It is often high-leveled. In order to get a Sharp poffin, you must have different berries (ex; Mico berry, Starf berry) and 4 other players.
You can't use poffins in this game
Egg case? There's no egg cases but there is a coin case, seal case,fashion case and poffin case.
The Poffin maker's house, it is left from the Pokemart in Hearthome City and ask the lady in front of the Poffin Maker. If you need a poffin case go to the Pokemon Fan Club and talk to the old man at the couch.
Go to Hearthome City, find the house that has a heart on top of the door. ( Also called Pokemon Fan Center) SIGGYh83r Talk to the chairman inside (sitting on the couch) and he will give you a poffin case.