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.

Erebus the Underworld Monarch · Emperor of Darkness Structure Deck 23064604/41

Erebus the Underworld Monarch (Emperor of Darkness Structure Deck 23064604/41), Ultra Rare. Market price $0.09, unchanged this week. Prices are estimates from TCGPlayer and Cardmarket, not guaranteed values.

You can Tribute Summon this card by Tributing 1 Tribute Summoned monster. If this card is Tribute Summoned: You can send 2 "Monarch" Spell/Trap Cards with different names from your hand and/or Deck to the Graveyard, and if you do, shuffle 1 card from your opponent's hand (at random), Graveyard, or their side of the field into the Deck. Once per turn, during either player's Main Phase, if this card is in your Graveyard: You can discard 1 "Monarch" Spell/Trap Card, then target 1 monster in your Graveyard with 2400 or more ATK and 1000 DEF; add it to your hand.

Weekly price history

Week	Market price
2026-W31	$0.11
2026-W32	$0.11
2026-W33	$0.13
2026-W34	$0.13
2026-W35	$0.13
2026-W36	$0.10
2026-W37	$0.10
2026-W38	$0.09
2026-W39	$0.09

Questions

How much is Erebus the Underworld Monarch 23064604/41 worth?

Erebus the Underworld Monarch from Emperor of Darkness Structure Deck (23064604/41) has a market estimate of $0.09, unchanged this week. Prices are estimates from TCGPlayer and Cardmarket.

Is Erebus the Underworld Monarch 23064604/41 rare?

It is an Ultra Rare from Emperor of Darkness Structure Deck, a 41-card set.

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