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.

Duality · Battles of Legend: Monstrous Revenge 39973386/104

Duality (Battles of Legend: Monstrous Revenge 39973386/104), Secret Rare. Market price $3.65, down 3.7% this week. Prices are estimates from TCGPlayer and Cardmarket, not guaranteed values.

Tribute 1 LIGHT or DARK monster; Special Summon 1 LIGHT or DARK monster from your hand or Extra Deck with the same original Type and Level, but a different original Attribute. During your Main Phase: You can banish this card from your GY, then target 1 LIGHT and 1 DARK monster in your GY; shuffle both into the Deck, then draw 1 card. You can only use each effect of "Duality" once per turn.

Weekly price history

Week	Market price
2026-W31	$5.25
2026-W32	$4.61
2026-W33	$4.24
2026-W34	$4.34
2026-W35	$4.34
2026-W36	$4.12
2026-W37	$4.11
2026-W38	$3.79
2026-W39	$3.65

Questions

How much is Duality 39973386/104 worth?

Duality from Battles of Legend: Monstrous Revenge (39973386/104) has a market estimate of $3.65, down 3.7% this week. Prices are estimates from TCGPlayer and Cardmarket.

Is Duality 39973386/104 rare?

It is a Secret Rare from Battles of Legend: Monstrous Revenge, a 104-card set.

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