What about Isochron Scepter?

Ozomoto, Defense Grid really does not work in a deck that has 27 instants and a few flash creatures. I'm not comboing off very quickly, and that's why I need to control the board before anyone else wins. Meekstone is worth considering, but right now I don't feel like it's more relevant than than any other card in the deck.Time Spiral is a nice card, although the its converted mana cost is a bit much. I will think about it, but I feel that I usually don't want to get rid of my hand, granted I'd get a new one. Thanks for the suggestions though!

Klone13, Isochron Scepter is interesting, and it could do well in my deck. It does need testing, as there's a lot of valuable cards that it could imprint, for example Vampiric Tutor and Mana Drain.

Dire Undercurrents is a exceptional good control card to combo with Oona considering the faeries produce by Oona are both blue and black.

Also Rune-Scarred Demon should be looking in to. True the mana cost can be a turn off but with Deadeye Navigator you can tutor up your win-cons in a pinch.

Dire Undercurrents is truly a great card in many Oona decks, but in this one I rarely cast her. Most of the time I cast Oona when I have infinite mana.

Rune-Scarred Demon really is just too much mana. Even the synergy with Deadeye Navigator to tutor up once costs 15 mana. That is too much. The fact that my combos only require two cards (most of the time) makes it so that I don't need tons of tutoring.

Thanks for the suggestions though, I always appreciate help!

might I suggest Tidespout Tyrant as you can use it to bounce any of your low mana rocks and recast them which would float you colorless mana in means to go infinite, also if your gonna play this heavy in combo you should have some tutors Vampiric Tutor Demonic Tutor Cruel Tutor Liliana Vess could speed the deck up and play more consistant while still keeping your control shell. hope this helps

Tidespout Tyrant is really risky, and the mana cost makes it quite unplayable in this deck. I must agree that the synergy with mana rocks is great, but it will be a dead card most of the time it's in my hand.

I already have Vampiric Tutor and Demonic Tutor in the deck. Liliana Vess is too slow and unpractical for this type of a deck. Cruel Tutor is kinda good, but for now I feel like it isnt needed in the deck. I'd rather get Imperial Seal sometime in the future.

Thanks for the comment!

I think Mystic Remora is something that can be replaced. I don't think you'll want to keep paying the mana after the 2nd counter and especially gets punished if they only go and play a creature spell.

Mystic Remora actually works great. Some people don't really care about it, as they just want to combo out fast. Once I drew about 10-15 cards from it. And when people are more careful about it, it works kinda like Time Warp because no one plays anything. Of course they can play creatures, but it usually still limits what they would play. Most of the times I pay the upkeep cost once or twice, as it has already paid me back.

Interesting points. How exactly do you play the deck? Turtle up until you can easily combo out or try to straight up tutor your combo out quickly? Also I'm missing a good chunk or the lands and some artifacts, and some more, mainly the more pricey ones. What in your opinion are the "core" cards of the deck? (Other than the combos)

I try to keep the control until I have enough tools to combo out. I need quite a lot of mana if I want to play all the combo pieces out on the same turn, and also keep some for countering. The deck doesn't usually win very fast, so it needs the control aspect to keep the game going.

Some of the more powerful cards in the deck other than combos are Yawgmoth's Will as it also usually wins the game for me, Necropotence for obvious reasons, Crucible of Worlds ensures my land drop with fetch lands, and Teferi, Mage of Zhalfir helps me a lot as I don't need to save so much mana for countering during my turn. Those were some specific cards that came to mind. Ramp is also very important for the deck, so for example Mana Crypt is an amazing card.

Seems like you have your deck spread a bit thin. I'd focus on one aspect. Either control or combo.

Well, what I'm trying is to control the board enough so that nobody else gets the upper hand before I am able to win. I feel that it's hard to make fast wins with this kind of a deck. What would you suggest to make this deck more combo-oriented? I'm not sure if I completely understand what type of changes this would require and how would it make the deck better.

I'd lose the infinite colorless mana combo in favor of cards like Sapphire Medallion, Reanimate, Shallow Grave, Intuition and Monastery Siege. I went as far as running Heartless Summoning in my deck despite the low creature count just increase my chances of to combo off early.

I'd also add one or two more win cons that won't rely on Oona.

I won't be needing Oona with my infinite mana if I have Braingeyser or Stroke of Genius in my hand. Drawing my entire deck lets me convert the colorless mana to colored. Sapphire Medallion is something that I have considered, but for now I have decided to use a mana stone instead. It is interesting though, so I might need to playtest it.

I feel like the creature-based cards like Heartless Summoning and Shallow Grave are good, but only in very specific occasions. I think adding those cards would make my deck less consistent, as I already have cards that don't do anything for me unless I start comboing off. Also, if I lose Palinchron in some way, those cards won't really do anything for me.

Monastery Siege is interesting, but I think the discard effect would hurt too much, as I don't have that much recursion in the deck. Intuition is already in.

I think you have a point in focusing more on Palinchron as a win con. I have considered dropping all the other combos out and put in cards that support it, like Sapphire Medallion and Reanimate. My infinite colorless mana combos are a lot faster though, so I'm not sure what should be done. Guess I need to playtest more.

Thanks for the suggestions, I really appreciate your help :)

You could use Peregrine Drake in addition to Palinchron.

+1 for this :3

I have thought about Peregrine Drake, but it would just another dead card in my hand if I'm not comboing. I need to keep the combo-only cards at minimum, so the decks consistency is at its maximum. Although Peregrine Drake costs less mana, I feel it wouldn't help me enough.

Thanks for the comment and +1! :)

Welp, this deck looks familiar.
Do you actually have all the cards now? :D
I kinda really want to build this deck for myself, but I don't want to be a copycat.

..dammit. I'm so jelly.

Looking through your decks, they actually look familiar too :D (along with your username). I own all the cards except Underground Sea, which I'm getting as soon as I can afford it.

Although the main idea behind all Oona combo-decks is the infinite mana, it can be varied in many ways. For example using Tidespout Tyrant to bounce your mana rocks to gain infinite mana is something I have thought. I've also seen Oona decks planned around Ad Nauseam. Those decks are straightforward combo-decks, and they can be quite fast and dangerous.

The reason I like Oona as a commander is that there is always an outlet for your infinite mana. Also, whenever I win with this deck I don't feel cheap at all, because it requires a lot of thinking and planning.

You seem to have an excellent collection of cards to make an efficient Oona deck (assuming you own all of the cards in your blue and black decks :D), so go for it!

Is Scroll Rack working for you? I took it out from my deck a long time ago because it never seems to do me much good. I'm thinking of giving it another try by replacing either Expedition Map or Chromatic Lantern.

I'm also considering using Mystic Remora and Rhystic Study (again). Are they reliable draw engines (in your experience)?

Scroll Rack is a great utility engine, especially with all the fetches and tutors I have. The deck needs a lot of card advantage, and Scroll Rack can replace some of the cards I don't need at certain points of the game. Although you're right that it works best only if you have enough cards in hand, and when you don't want to keep some of the cards in it. I'd suggest trying out again, making strategies with it and using it cleverly. For now, I have been quite happy with it (and it also has a great synergy with necropotence).

Mystic Remora is great, and I have always gotten cards with it. Remora works also as a control card, since some people don't want you to draw anything more than they want to play themselves.

Rhystic Study has the same aspects as Remora, and I like it being a more consistent. I have been thinking if I should replace it with Phyrexian Arena, but Rhystic Study has a lot more efficient mana cost, it usually control what people would play, and it might give me more card advantage. It depends quite a lot what type of meta you play in, so try it out, it could work for you really well.

Decided to run Scroll Rack, Mystic Remora, Rhystic Study and Phyrexian Arena. Lol. Hopefully that generates the card draw/advantage I so desperately need.

Hopefully it is :D Maybe I'll also put Phyrexian Arena in the deck, not sure what should go out though, Rhystic Study is still a very nice card. Need to playtest more!

@cosmicteapot - yeah, I have all the cards I use in my decklists..

The thing is.. I already tried making Oona once, I liked it a lot. It did everything I wanted it to.. Except that it wasn't Memnarch.

I kinda really like my Memnarch, so I'm trying to make it as competitive as I can. I'm pretty sure it won't be nearly as good as your Oona, but one can dream.. right? :D

(I'd appreciate it if you could give it a look sometime and maybe tell me what you think of it.)

I love seeing the subtle changes every few days, they're always interesting! Are these changes solid improvements to the deck or purely for your meta?

Fellwar Stone seems underpowered here. Chrome Mox and Mox Opal might be better options.

I also took out Necropotence and Crucible of Worlds from my Oona deck since they don't seem to perform anywhere close to how they do in other decks.