Pokémon Diamond and Pearl/Hearthome City

Hearthome City is not only the home to Sinnoh's Contest Hall, but features Amity Square, a park where you can walk your cute Pokémon.

Tasks

 * Upon entering Hearthome City, a will come running towards you. Stall it long enough for its trainer, Keira, to get it back in its Poké Ball, and she will ask you to come to the Contest Hall so she can thank you properly.
 * If you are having trouble finding the Contest Hall, speak to the person in front of the Pokémon Fan Club. He will escort you to the Contest Hall.
 * At the Contest Hall you will run into Keira, along with your mom. To get you started, your mom will give you a dress or tuxedo, and Keira will give you a fashion accessory, the Glitter Powder. You will also receive a Smooth Poffin from a man near the counter inside.
 * The woman found in the house beside the Pokémon Center is Bebe. Like Lanette and Bill of the previous Pokémon games, she is the storage system administrator. Return to after you beat the game and have received the National Dex and she'll give you an . Platinum version: Bebe will provide you an Eevee whenever you decide to talk to her, as opposed to needing to beat the game beforehand.
 * In the building to the right of the Poké Mart is the Pokémon Fan Club. Speak to the Fan Club's chairman and he will give you a Poffin Case. A lady in the fan club will check how much your lead Pokémon likes you, and a Jubilife TV reporter will interview you here.
 * Visit the second house to the right of the Poké Mart. On the second floor you will find a woman who will give you the Shell Bell.
 * The house to the left of the Poké Mart is the Poffin House. With your Poffin Case in hand, enter and bake to your heart's desire.
 * Talk to the man near the southeast gate to receive an egg containing a ! Platinum version: the man near the Southeast gate will not give you an egg. He'll just ramble on about Professor Elm.

Poké Mart

 * Poké Ball: [[File:Pokebuck.png]]200
 * Heal Ball: [[File:Pokebuck.png]]1000
 * Net Ball: [[File:Pokebuck.png]]1000
 * Nest Ball: [[File:Pokebuck.png]]1000
 * Potion: [[File:Pokebuck.png]]300
 * Super Potion: [[File:Pokebuck.png]]700
 * Antidote: [[File:Pokebuck.png]]100
 * Awakening: [[File:Pokebuck.png]]250
 * Paralyze Heal: [[File:Pokebuck.png]]200
 * Burn Heal: [[File:Pokebuck.png]]250
 * Ice Heal: [[File:Pokebuck.png]]250
 * Repel: [[File:Pokebuck.png]]350
 * Escape Rope: [[File:Pokebuck.png]]550
 * Heart Mail: [[File:Pokebuck.png]]50

Gym badge #5
You may only battle Fantina after talking to Cynthia's grandma in Celestic Town and getting HM03, Surf.

In Platinum, you can find Fantina in the Contest Hall lobby. After talking to you, she'll run off to wait for you in the gym.

The Hearthome Gym features a series of question that you must answer to move on. On each floor is a sign bearing the question and three doors that are labeled with answers to those questions. If you move through the gym getting all questions right, you won't have to face any trainers on your way to challenge the leader, Fantina. The answers to the questions in order are: 15, 40, 39, and 15.
 * Gym Leader: Fantina
 * (Lv.32)
 * (Lv.34)
 * (Lv.36)
 * Reward: Relic Badge, TM65

In Platinum, the Hearthome Gym is a little different. You'll navigate a pitch-black labyrinth with a flashlight, looking for the singular blue tile in a given room. Each blue tile will have a symbol on it. At the end of each room is a series of doors with red tiles in front of it. Go through the door whose red tile has the same symbol as the blue tile you saw earlier to proceed. The trainers in this gym have flashlights too, but you only battle them when they catch you in their flashlight, or you catch them in yours. It is possible to fight Fantina here, but be warned: you might find yourself unprepared to face her this early in the game. But, defeating her is possible, and necessary to continue the Platinum storyline.

Fantina carries all Ghost-type Pokémon, so if you have a strong Dark-type move, you can easily breeze your way through the fifth gym leader.