Rhilis: Yep, there are a few cards that have been going in and out of the deck for a while now (Shred Memory for example). I always try to get solid improvements in the deck, making it more consistent and efficient. It's quite hard, so testing different cards is the best option.

Megalomania: I quite like Fellwar Stone. Most of the times it produces me blue mana right away, and colored mana is extremely important for this deck. It also comes into play untapped, which is a big plus.

Mox Opal is definitely an option, but I want to have more artifacts in the deck in order to use it. There are even some artifacts like Grim Monolith and Basalt Monolith which I'm really careful to cast, since they are important combo pieces. That's why getting metalcraft is difficult with the amount of artifacts I currently have in the deck.

I have though about Chrome Mox and Mox Diamond, but I'm a little hesitant about the card disadvantage they make. I will keep them in mind though. I would interested to hear how Chrome Mox and Mox Opal have worked for you.

I've actually considered to drop Palinchron combos from the deck, since they require too many lands to work. I think I'd rather invest in the artifact combos, since they have been my main win condition in most of the games. Palinchron and cards like Deadeye Navigator have mainly been dead cards for me. If I drop them out of the deck, I might replace them with cards like Mox Diamond, Mox Opal and more tutors like Transmute Artifact. I still need to test more to be sure.

Necropotence and Crucible of Worlds are amazing in this deck, but I understand if your deck gains disadvantage from exiling cards, and Crucible might be too slow.

Crucible of Worlds is one of the reasons I run 7 fetchlands and Strip Mine (also I'm getting Wasteland at some point). The deck does not enjoy mana screw, and Crucible provides me the land drops I need.

And Necropotence just wins games for me. It keeps my hand full, and if I have Reliquary Tower on the field, the opponents don't have much time left.

Sounds like you're going the Ad Nauseam route. I considered doing the same at one point but my current setup is doing so well I just couldn't find it in me to take it apart. I strongly suggest you try it as it fits what you are trying to do here.

With all my cmc reduction, casting Palinchron isn't really that big of a problem although I mostly rely on reanimation to put it into play.

As for the Moxes, they have been working well for me. My deck generates a good amount of card advantage so I normally don't have problems pitching cards for them.

Necropotence is one of my favorite cards ever. Its drawback is just too intrusive to the deck's current gameplay. It does appear to favor yours though. Come to think of it, the Moxes would further improve your chances of comboing off after Necro. Dropping the Palinchron-based combos would do you well. Your deck will most probably end up looking like one of the cool Oona decks I saw on this site but if that doesn't bother you, you should definitely go for it.

Crucible of Worlds just isn't as strong in as it is in . Even with Strip Mine, I still feel you'd be better off investing in something that will help you combo off.

Bitterblossom

Why do you think that Bitterblossom could be good? I guess it makes valuable blockers as my deck is often targeted first, but other than that it does not do much for me.

You know, I see infinite color mana combos and just think in these colors.......Mind Grind anyone?

Mind Grind is a good card, but in this deck it would not do much. I already have quite a bit of infinite mana outlets, and they all do something nice on their own. Mind Grind on the other hand does not give me much of a benefit. Exsanguinate would be better, but it has same problem: it's a dead card for me until I can assemble a combo, which takes a lot of preparation.

Dire Undercurrents is insane with Oona.

Dire Undercurrents is a great great, but this deck rarely casts its commander so it would not do much. In the more control-based, slower strategies it could work very well.

Have you ever thought of going the Doomsday route?
I've seen quite a few Oona lists lately that run it.. (To how much success, I don't know)

Glad you decided to take the Ad Nauseam route. How is it working for you so far?

I think you can River of Tears with Mana Confluence which is more reliable or Crystal Vein if you want speed.

morimus: I have thought about Doomsday, but going that route is too risky for my liking, and it requires too many dead cards. It can be very effective in some games, but in my experience Doomsday combo is just too easily countered by opponents.

Megalomania: Ad Nauseam has been working quite well for me. I have some cards from this decklist replaced for cards like Ponder and Preordain (general Ad Nauseam cards) to make my average CMC smaller. I have thought about adding Dark Confidant, but I'm a little hesitant about life loss (I usually lose a lot of life during games). Same goes for Mana Confluence. It's good, but I'm not sure if the loss of life would hurt me too much. I guess I have to test it out! Crystal Vein is just too unconsistent for this deck, but of course it has its advantages.

A couple of questions:

Have you thought about running Cunning Wish to maybe hide a few of your more situational instants away & get something else to fill the slots?
What about Mental Misstep ? Seems like it could be useful in a tutor- & fast mana -rich meta, which I assume yours is?

I haven't considered Cunning Wish very much, mostly because I feel that having a wishboard is unpractical :D Also some playgroups don't accept wishboards. But I think I should give Cunning Wish a chance, as it could provide useful. Just need to check what kind of a wishboard would suit me the best!

I really like Mental Misstep as a card and I have tried it a few times. Against my main playgroup it doesn't work well, as my deck is fastest one of them, but when I play against more combo-oriented players it works really well. For now I won't put Mental Misstep in the deck, but I'll keep it in mind as I really would love to play it :D

Thanks for the suggestions, Cunning Wish got me interested!

While the build seems relatively solid overall, using artifacts as your only win condition is dangerous. There is a lot of very cheap artifact hate and you have no way of dealing with Krosan Grip which is not only common but leaves you dead in the water.

I would recommend putting at least one non artifact infinite mana combo in the deck to increase resilience.

Other than that the list looks good.

Yeah, it's true that only artifacts as win conditions is a big risk. Krosan Grip is a huge threat, but sometimes manageable (for example setting up the combo when opponents don't have any green mana to use). Having an efficient non-artifact combo would be great, but I haven't found any that would synergize well with this list as I want to keep the dead cards in minimum.

Good thing is that I still have one or two tries to win with a different combo if the first one is disrupted. And even after that I have Yawgmoth's Will, so most of the times I should be fine in this regard.

Cool list. I have an Oona deck that's kinda similar called The Deck First, I have a few questions. Are you sure that Rings of Brighthearth allows you to go infinite with Basalt Monolith? It says non-mana abilities and Basalt Monolith is a mana ability. Also, why do you need other finishers to use once you have infinite mana? Oona seems like all you need because you'll always have access to her and you can just replay her if she gets countered, provided you have access to mana that isn't colorless. Plus, Oona can kill all opponeents, Stroke of Genius only kills one.

This leads me to some minor recommendations. I'd recommend looking in to Palinchron/High Tide (with 4 or more Islands) and Palinchron/Deadeye Navigator. Those give you infinite blue mana, making the game pretty much unloseable. The thing is with Power Artifact shenanigans, to kill a field of three opponents you need 2 blue mana to play Power Artifact, 3 blue or black to play oona and 3 blue or black to activate the ability once for each opponent (8 total) none of which is provided to you by the infinte colorless. Ok, maybe Ooona was already in play, bringing that number down to 5. And I mean it seems really dangerous to throw down the infinite colorless combo and not be able to immediately use Oona in the same turn.

You copy the "untap" ability, not the mana ability.

ragincajun129: The benefit of Stroke of Genius over Oona is that it kills opponents then and there. With Oona, they still get an upkeep to do stuff before they die (which some decks can win in).

The other thing is if you're ready to combo however dont have removal then and there, if facing a Nevermore or Linvala, Keeper of Silence, you first have to draw into removal before comboing off. It helps to have some form of backup wincon.

ragincajun129: Rings of Brighthearth copies Monolith's untap ability, and after the first untap resolves I tap Monolith for 3 mana again and repeat to infinity.

Unless I'm playing 1vs1, I'll cast Stroke of Genius targeting myself. This way I'm able to kill all the opponents easily on the same turn. I have multiple win conditions because, as you noticed yourself, Oona itself costs 4 colored mana to get rid of one opponent. Most of the times I can't afford that much, as I have to keep blue mana open for counterspells.

I had Palinchron combos originally in this deck, but took them out because they are too mana heavy, and surviving till I have enough lands in play is tough without any land ramp. Palinchron and Deadeye Navigator are also completely dead cards for me if I'm not comboing. I figured that focusing on the artifact combos would be for the best, as they are relatively cheap to set up. (Palinchron is also a huge risk with Ad Nauseam in the deck)

Thanks for the comment, I appreciate it! :)

You have given me much to think about. I'm starting to see that Oona pilots are somewhat of an elite fraternity. I'll be doing some testing.

The benefit behind Palinchron however is that it gives you access to coloured mana. You can use it post combo as a mana converter (assuming you have UU open). Even if it just he's you black mana, you can make Oona work off that. But I get that 7 life is a lot to pay from an Ad Nauseam.

True. I have wanted to use Ad Nauseam in my deck for a long time but can't because my core pieces include cards like Palinchron and Future Sight.

Is this deck purely competitive or do you run this deck casually as well? I had a more budget version of a deck like this but it kept drawing too much hate. Any advice about avoiding making a bitter crowd?

I'm keeping it as competitive as I can, and I won't replace any cards for different games. Usually my playgroup can deal with this deck, so there won't be any grumpiness.

Combo decks tend to get a lot of (also sometimes quite irrational) hate. Sometimes even if you combo out very late in the game the people might get upset, feeling like they couldn't have done anything to stop you. So it might be hard to avoid bitterness only by playing different cards. I'd maybe try explaining people my views on combo decks and discuss about it (maybe come up with some kind of a compromise).

I have decided that I will play what I want to play, and fortunately my main playgroup doesn't mind. If the games start to become way too unbalanced, then maybe I might change to my second deck or borrow one. It's fun to annilihate everyone for a couple of games, but it gets boring quickly :D

The deck deserves an Imperial Seal.