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.

Cosmic Blazar Dragon · Duelist Saga 21123811/100

Cosmic Blazar Dragon (Duelist Saga 21123811/100), Ultra Rare. Market price $0.81, up 1.3% this week. Prices are estimates from TCGPlayer and Cardmarket, not guaranteed values.

1 Tuner Synchro Monster + 2+ non-Tuner Synchro Monsters Must be Synchro Summoned. (Quick Effect): You can banish this card until the End Phase to activate 1 of these effects; ● When your opponent activates a card or effect: Negate the activation, and if you do, destroy that card. ● When your opponent would Summon a monster(s): Negate the Summon, and if you do, destroy that monster(s). ● When an opponent's monster declares an attack: Negate the attack, then end the Battle Phase.

Weekly price history

Week	Market price
2026-W31	$0.87
2026-W32	$0.82
2026-W33	$0.79
2026-W34	$0.82
2026-W35	$0.82
2026-W36	$0.84
2026-W37	$0.79
2026-W38	$0.80
2026-W39	$0.81

Questions

How much is Cosmic Blazar Dragon 21123811/100 worth?

Cosmic Blazar Dragon from Duelist Saga (21123811/100) has a market estimate of $0.81, up 1.3% this week. Prices are estimates from TCGPlayer and Cardmarket.

Is Cosmic Blazar Dragon 21123811/100 rare?

It is an Ultra Rare from Duelist Saga, a 100-card set.

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