Like the main series of games, Pokémon Trading Card Game has you able to receive special cards from various people around TCG Island

Grass Club - Trades
Location: Grass Club

When you speak to this person in the Grass Club, located in the middle of the club's lobby, you will find that she wants to trade cards with you. There are three trades that can be done in this manner, and you can only do one each time you load your save file up. One of these cards is a promotional card.

Your Card Her Card
Fire Club - Hidden Card
Location: Fire Club

This particular gift is an odd one. When you speak to this character, he will ask you for all the Energy cards that you have which currently aren't attributed to your deck. If you give them to you, he'll give you a hint about a special card. The card is two steps to the left of the bookcase. Interact with the wall, and you'll get a special promotional card

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Water Club - Trades
Location: Water Club

At the table in the Water Club is another person who wishes to trade. This one has no pre-requisites and is a simple one-off trade. She will ask for you to trade your Lapras for her rare Arcanine card

Your Card Her Card
Lightning Club - Trades
Location: Lightning Club

In the Lightning Club is another character who will trade cards with you. Like before, there is no pre-requisite to this trade. Simply, he wants a Level 35 Electabuzz card for his special rare Electabuzz promotional card

Your Card His Card
Psychic Club - Special Gift
Location: Psychic Club

At the table in the lobby in the Psychic Club, you will find Pappy, who will offer you a very rare promotional card once you have defeated Murray, the Club Master.

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Fighting Club - Special Gift
Location: Fighting Club

At the table in the lobby in the Fighting Club, you will find this character. Every time you load up your save file, he will ask for a specific card chosen at random from Graveler, Parasect, Rapidash, Weezing or Omastar. Once you have given him five cards, he will give you this special card.

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Various - Ronald
Location: Various

Each of the times you battle your rival, Ronald, you will receive a special rare card for doing so. Two of these instances involve participating in the Challenge Cup, while the other two are just standard battles.

Picture Name Battle Instance
Jigglypuff First Battle
Mewtwo First Battle in Challenge Cup
Super Energy Retrieval Battle after earning 5 medals
Mew Second Battle in Challenge Cup
Various - Imakuni?
Location: Various

A strange fellow who is talked about by various people in the Water Club. He appears at in one of the Clubs at random upon loading your save file and is instantly recognizable by his animal costume. If you talk to him, he challenges you. He will give out one of every booster pack on his defeat, and if you beat him thrice in a row he will give you a special card that is based upon him.

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Mr. Ishihara - Trades
Location: Ishihara's House

Like most of the Pokemon RPGs you can meet a member from The Pokémon Company in the game, in this case producer Tsunekazu Ishihara. He resides at his home at the far top left of the map. Mr. Ishihara will organize trades with you throughout the game where you can receive the very rare Pikachu promo cards in exchange for rare colorless Pokemon.

Your Card His Card