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.

Union Combination · Speed Duel: Battle City Box 300302020/223

Union Combination (Speed Duel: Battle City Box 300302020/223), Common. Market price $0.39, unchanged this week. Prices are estimates from TCGPlayer and Cardmarket, not guaranteed values.

Once per turn, during your Main Phase, you can place 1 card from your hand on the bottom of your Deck, then Special Summon 1 LIGHT Machine Fusion Monster from your Extra Deck, that cannot be Fusion Summoned, using monsters from your field or GY as material, ignoring its Summoning conditions. For the rest of this turn, your opponent takes no damage.

Weekly price history

Week	Market price
2026-W31	$0.34
2026-W32	$0.34
2026-W33	$0.31
2026-W34	$0.31
2026-W35	$0.31
2026-W36	$0.33
2026-W37	$0.33
2026-W38	$0.39
2026-W39	$0.39

Questions

How much is Union Combination 300302020/223 worth?

Union Combination from Speed Duel: Battle City Box (300302020/223) has a market estimate of $0.39, unchanged this week. Prices are estimates from TCGPlayer and Cardmarket.

Is Union Combination 300302020/223 rare?

It is a Common from Speed Duel: Battle City Box, a 223-card set.

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