This is my take on a Oona, Queen of the Fae build.

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"Is the deck competitive, casual or what?"

Well, This is not the easiest question to begin with. I would say somewhere between the two, although she is a little closer to the competitive end of scale for sure. She won't perform well in cutthroat metas where games are decided somewhere around turn five, but she could maybe outclass opponents in more casual groups. On a scale from 1 (pure casual) to 10 (hermit druid power level cuttthroat deck), I would give her a 7.5 (or 8 if I would be very optimistic). Still, I would say that she is a very strong deck and does pull out wins.

Although she has pulled turn 2 wins on multiple occasions and even has the potential for a turn 1 win in her, we have to remember at her heart she is a control build with a combo thrown in and NOT the other way around.

I think this build speaks of the pure hatred within EDH players' hearts and their unbearable desire to make everyone miserable.

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"Why would you play this deck?"

She’s a straight up control/prison deck that locks everyone out of having fun...Then combos out late game if desired. It's a complete troll player's wet dream. She has access to tutors, draw, mass/spot removal, and some combos incase you just want to end it all.

"Why wouldn't you play this deck?"

EDH is your way to making new friends, and you don't like bringing hate to the table. In which case you should probably be playing the purple hippo.

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Some notable interactions:

Rings of Brighthearth + Xiahou Dun, the One-Eyed : At the cost of 1 creature and only 2 mana you get any 2 black cards back from the 'yard...Including Xiahou himself if you wanted.

Basalt Monolith + Rings of Brighthearth + Sensei's Divining Top : How it works is you create Infinite Mana with Monolith and Rings, then you use Rings to copy the draw ability on Top. This allows you to draw a card, then the second copy allows you to get Top back. Recast Top with the Infinite Mana and rinse and repeat by drawing your whole deck.

Grim Monolith + Power Artifact or Basalt Monolith : Reducing the untap cost of 1 of both the Monoliths by 2, netting you 1 Mana each time to go infinite.

Basalt Monolith + Rings of Brighthearth : Pay 2 to use Rings to copy the untap ability of the Monolith. It allows you to tap it twice to create 6 mana. Use 3 mana to untap Tthe Monolith, then 2 mana to reuse the ability of Rings on the Monolith to continue the loop...It nets you 1 colorless mana each time.

Cabal Coffers + Deserted Temple + Rings of Brighthearth : You activate the Coffers to produce 6 mana, activate Temple's second ability targeting Coffers, and copy the ability with Rings to target Temple, you end up with both lands untapped and 3 Black mana. Repeat for infinite mana.

Deserted Temple + Rings of Brighthearth + Scorched Ruins : If you tap Ruins for 4 mana, activate Temple's second ability targeting Ruins, and copy the ability with Rings to target Temple, you end up with both lands untapped and 1 mana. Repeat for infinite mana.

Bitterblossom + Contamination or Contamination + Reassembling Skeleton : This will lock everyone into Black mana. On your upkeep, put your triggers on the stack and either sac the token created from Bitterblossom or by using the ability of Reassembling Skeleton from the graveyard to sac that instead.

Crucible of Worlds + Death Cloud : Pretty much resets the game for the table, and sets you up for the win. Leaving everyone to scramble back while you still consistently hit your land drops.

Crucible of Worlds + Strip Mine or Crucible of Worlds + Wasteland : Keeps opponents problematic lands under control, or just locks them out of the game entirely.

Disclaimer:

Your opponents will hate you, but the salt needs to be real sometimes.

Disclaimer P2:

Yes, Black Braids is banned. My playgroup are adults and don’t mind.

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