Can I build a deck together with friends on TCGSwap?

Yes. Every deck on TCGSwap has a Collaboration Space. You can invite up to 5 friends; they can suggest card changes, discuss ideas, and playtest proposals. You review and apply suggestions before anything changes in your deck.

How does deck collaboration work?

It works like a pull request for your deck. Collaborators open the deck editor, make their proposed changes, and submit a suggestion with a note. You get notified, open the comparison view to see exactly what they changed, and choose to apply all, cherry-pick individual cards, or decline. Nothing changes in your deck until you approve it.

Can collaborators chat and discuss the deck?

Yes. The Collaboration Space has a shared group discussion thread for the whole deck, plus a per-suggestion Q&A thread for each proposal. You can @mention teammates and link specific cards inline.

Is collaborative deck building free?

Yes, collaboration is free for all TCGSwap users during beta. You can invite up to 5 collaborators per deck.

Does TCGSwap work for MTG, Pokémon, Yu-Gi-Oh and One Piece collaboration?

Yes. The Collaboration Space supports all four games — Magic: The Gathering, Pokémon TCG, Yu-Gi-Oh and One Piece. Format validation and card prices are included for each game.

Professor Oak's New Theory · HeartGold SoulSilver 101/123

Professor Oak's New Theory (HeartGold SoulSilver 101/123), Uncommon. Market price €0.20, down 13.0% this week. Illustrated by Ken Sugimori. Prices are estimates from TCGPlayer and Cardmarket, not guaranteed values.

Card text

You can play only one Supporter card each turn. When you play this card, put it next to your Active Pokémon. When your turn ends, discard this card. Shuffle your hand into your deck. Then, draw 6 cards.

Weekly price history

Week	Market price
2026-W36	€0.24
2026-W37	€0.24
2026-W38	€0.23
2026-W39	€0.20

Printings & variants

Normal — $0.74
Reverse Holo — $6.96

Questions

How much is Professor Oak's New Theory 101/123 worth?

Professor Oak's New Theory from HeartGold SoulSilver (101/123) has a market estimate of €0.20, down 13.0% this week. Prices are estimates from TCGPlayer and Cardmarket.

Is Professor Oak's New Theory 101/123 rare?

It is an Uncommon from HeartGold SoulSilver, a 123-card set.

Is Professor Oak's New Theory 101/123 tournament legal?

Professor Oak's New Theory 101/123 has rotated out of the current formats.

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