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.

Poseidra, the Storming Atlantean · Supreme Darkness 99193444/101

Poseidra, the Storming Atlantean (Supreme Darkness 99193444/101), Quarter Century Secret Rare. Market price $0.27, down 95.5% this week. Prices are estimates from TCGPlayer and Cardmarket, not guaranteed values.

While you control a monster, except "Poseidra, the Storming Atlantean", your opponent's monsters cannot target this card for attacks. You can only use each of the following effects of "Poseidra, the Storming Atlantean" once per turn. You can send 1 other WATER monster from your hand or face-up field to the GY; Special Summon this card from your hand. If this card is Normal or Special Summoned: You can send 1 "Atlantean" or "Mermail" monster from your Deck to the GY, then target 1 card your opponent controls; return it to the hand.

Weekly price history

Week	Market price
2026-W31	$6.19
2026-W32	$7.40
2026-W33	$5.86
2026-W34	$5.74
2026-W35	$5.74
2026-W36	$5.96
2026-W37	$0.27

Questions

How much is Poseidra, the Storming Atlantean 99193444/101 worth?

Poseidra, the Storming Atlantean from Supreme Darkness (99193444/101) has a market estimate of $0.27, down 95.5% this week. Prices are estimates from TCGPlayer and Cardmarket.

Is Poseidra, the Storming Atlantean 99193444/101 rare?

It is a Quarter Century Secret Rare from Supreme Darkness, a 101-card set.

Browse more Yu-Gi-Oh cards · All Supreme Darkness cards · Build a deck · Track your collection