Some of the creature based combos like Palinchron + Deadeye Navigator are more difficult to reliably get in hand and play IMO, I would focus on the small cost artifact-based infinite combos first and only slot in some of these if they fit. Palinchron + Phantasmal Image is my favourite amongst them. You will need a lot of slots open for disruption, interaction and protection cards. Your main vulnerabilities will be locking Urza off the board, or removal of combo pieces from your deck. There should be enough redundancy in combo pieces to prevent the latter, but Pithing Needle or similar disruption would lock down Urza.
You could also look at something like Vedalken Archmage + Cheerios to draw through your deck for combo pieces, as an alternative to relying solely on tutors. I have a Jhoira, Weatherlight Captain cEDH deck that essentially does this, it's almost like artifact storm.
Hah! Yeah that's an excellent example. Omnipotence is another contentious one, I've heard it pronounced 'omni-po-tence' and 'om-nip-o-tence'. When you've been saying it one way for so long, it can sound so odd a different way!
Was watching an old Command Zone episode, and noticed that Josh pronounces Ghave as 'Gah-vay', instead of like cave, grave, brave, stave, etc. etc. I remember coming across players with other pronunciations in Magic that I found odd, such Myr as 'Mire', and Nissa as 'Nee-sa'.
This is not to claim what is right/wrong in pronunciation, there will always be differences in pronunciations based on accents and languages. But have you ever heard a word in magic pronounced in a way that made you stop and think... wait, that sounded a bit odd, is that how it's supposed to be pronounced?
Does he work with undying creatures? You sac the creature as the cost, then the undying trigger goes on the stack, then his ability to put a -1/-1 counter, so the -1/-1 resolves first so it doesn't work? I might be missing a rules thing there.
You are missing that you pick targets before paying. Therefore, doing that would counter the abillity. To get it to work you need two creatures with undying.
I've been testing out Serra as an alternative playgroup-restricted Commander of my Avacyn, Angel of Hope angel tribal deck.
There are some interesting interactions I've found. Notably, with sufficient ramp you can have her in play turn 3/4 for a +2, then in the next turn make a -6 emblem, and recast Serra again for a -3 Angel.
Seems fairly good, but doesn't have quite the same impact as building up to Avacyn. Still requires more testing to figure out if it's worthwhile. Will be tough, as most mono-white decks can be rather tedious to play with such limited draw potential. Decks like Sram probably being the exception.
When SoI released in 2016, I got fairly hyped over Sin Prodder. Red was generally poor at generating card advantage, and in the right deck an opponent taking the damage to deny the draw can still be positive for your game plan.
However, since then red has seen a significant shift across multiple sets, increasing it's card advantage potential. Is Sin Prodder good in a Neheb deck? Yeah, of course it is. Are there arguably better (more consistent) cards that could be in that slot? Also yes.
+2 Creatures you control with flying get +1/+1 until end of turn.
-3 Create a 4/4 white Angel creature token with flying and vigilance. Essentially a Serra Angel token.
-6 You get an emblem with "If you control a creature, damage that would reduce your life total to less than 1 reduces it to 1 instead. Essentially a Worship emblem.
I think you need to specify some limitations on your proposed card if you want a more informative response.
A vanilla "You win the game" on a sorcery would be too powerful at any cost, mana cost is a false restriction, it is relatively easy to overcome.
If it was instead "You win the game, if you meet condition X", well there are already plenty of cards just like that, with varying CMC and varying difficulty in achieving their condition.
Need a little bit more context to provide specific feedback, as your deck seems to be built mostly casual, but you sound like you want it to be fast and competitive.
Is your meta casual, semi-casual, competitive?
What mulligan rules does your playgroup use?
What is the strategy for this deck? You seem to have tokens, +1/+1 counters, flicker, legendary, counter spells, spell doubling, and turn manipulation. More strategies in a deck dilutes their individual effectiveness, you would benefit from focusing on fewer themes.
For a casual/semi-casual deck, your land count is a little low, even with the number of rocks you have. I assume this may be compensated for with a lax mulligan rule in your playgroup, as you can't reliably cast mana rocks if your hand has too few lands.
For a competitive deck, your average CMC is very high. Decks with higher CMC cards tend to cheat mana costs (e.g. Narset), otherwise another check over your curve is probably a good idea. Would you really hold up that much mana for those high CMC counter spells? Do you consistently have enough mana to pay the CMC and Riku's ability on those high CMC creatures?
It is focused around token generation, and is designed to function independent of Riku. My average CMC is higher than yours, but I have 36 lands and 10 other mana sources.
I use a template that ensures I have sufficient mana, targeted removal, mass removal, card draw, and card advantage.
Why does everybody hate Exotic Orchard? Haven't heard it mentioned. It's literally the second best land after Command Tower.
I personally prefer Reflecting Pool and Meteor Crater over Exotic Orchard. The Orchard isn't a bad card, but I feel that I have more control over colours with the Pool and Crater, even if they may be less reliable sources of mana. I have Exotic Orchard in one of my 5 colour decks, and my Narset deck.
Exotic orchard and CT are top 30, sure, but top 5?!?! When I can play strip mine and volrath's stronghold? Taiga, tundra, etc?
No way, get real.
The ABU dual flex isn't very helpful, not everyone can afford to include them. If you think ABU duals are standard for Commander, YOU need to get real.
The underlying package essentially just needs infinite mana as you've pointed out. Trophy Mage for your Basalt Monolith, Arcum Dagsson for your Rings of Brighthearth. Arcum Dagsson needs a few artifact creatures, maybe something like Sai, Master Thopterist or similar may be suitable. There are a bunch of cards that synergise very well with Arcum Dagsson. Tribute Mage also gets you your Isochron Scepter, Mystical Tutor for Dramatic Reversal. All of these tutors are essentially second copies of the core combo cards you need.
Some of the creature based combos like Palinchron + Deadeye Navigator are more difficult to reliably get in hand and play IMO, I would focus on the small cost artifact-based infinite combos first and only slot in some of these if they fit. Palinchron + Phantasmal Image is my favourite amongst them. You will need a lot of slots open for disruption, interaction and protection cards. Your main vulnerabilities will be locking Urza off the board, or removal of combo pieces from your deck. There should be enough redundancy in combo pieces to prevent the latter, but Pithing Needle or similar disruption would lock down Urza.
You could also look at something like Vedalken Archmage + Cheerios to draw through your deck for combo pieces, as an alternative to relying solely on tutors. I have a Jhoira, Weatherlight Captain cEDH deck that essentially does this, it's almost like artifact storm.
Hah! Yeah that's an excellent example. Omnipotence is another contentious one, I've heard it pronounced 'omni-po-tence' and 'om-nip-o-tence'. When you've been saying it one way for so long, it can sound so odd a different way!
This is not to claim what is right/wrong in pronunciation, there will always be differences in pronunciations based on accents and languages. But have you ever heard a word in magic pronounced in a way that made you stop and think... wait, that sounded a bit odd, is that how it's supposed to be pronounced?
Why have only two? Why not have all undying creatures? Mikaeus the Unhallowed
Play artifacts, draw cards, return artifacts to hand, play MORE artifacts. Rinse repeat win
There are some interesting interactions I've found. Notably, with sufficient ramp you can have her in play turn 3/4 for a +2, then in the next turn make a -6 emblem, and recast Serra again for a -3 Angel.
Seems fairly good, but doesn't have quite the same impact as building up to Avacyn. Still requires more testing to figure out if it's worthwhile. Will be tough, as most mono-white decks can be rather tedious to play with such limited draw potential. Decks like Sram probably being the exception.
Alternatively, a mill and/or alternative wincon strategy may spice things up.
However, since then red has seen a significant shift across multiple sets, increasing it's card advantage potential. Is Sin Prodder good in a Neheb deck? Yeah, of course it is. Are there arguably better (more consistent) cards that could be in that slot? Also yes.
+2 Creatures you control with flying get +1/+1 until end of turn.
-3 Create a 4/4 white Angel creature token with flying and vigilance. Essentially a Serra Angel token.
-6 You get an emblem with "If you control a creature, damage that would reduce your life total to less than 1 reduces it to 1 instead. Essentially a Worship emblem.
https://m.imgur.com/ULHVe3D
It's finally happening, a Serra planeswalker! To be printed in the upcoming Modern product.
Thoughts on Serra in Commander? Would you allow someone in your playgroup to house rule Serra as a Commander?
A vanilla "You win the game" on a sorcery would be too powerful at any cost, mana cost is a false restriction, it is relatively easy to overcome.
If it was instead "You win the game, if you meet condition X", well there are already plenty of cards just like that, with varying CMC and varying difficulty in achieving their condition.
Is your meta casual, semi-casual, competitive?
What mulligan rules does your playgroup use?
What is the strategy for this deck? You seem to have tokens, +1/+1 counters, flicker, legendary, counter spells, spell doubling, and turn manipulation. More strategies in a deck dilutes their individual effectiveness, you would benefit from focusing on fewer themes.
For a casual/semi-casual deck, your land count is a little low, even with the number of rocks you have. I assume this may be compensated for with a lax mulligan rule in your playgroup, as you can't reliably cast mana rocks if your hand has too few lands.
You have very few targeted removal spells, and no mass removal that I can see. Curse of the Swine and Descent of the Dragons contribute towards a token-focused strategy if that's what you're going for, while Decimate, Song of the Dryads and Cyclonic Rift are just always good in these colour combinations. I quite like the new Cindervines too.
For a competitive deck, your average CMC is very high. Decks with higher CMC cards tend to cheat mana costs (e.g. Narset), otherwise another check over your curve is probably a good idea. Would you really hold up that much mana for those high CMC counter spells? Do you consistently have enough mana to pay the CMC and Riku's ability on those high CMC creatures?
If you're interested, this is my Riku build:
https://tappedout.net/mtg-decks/riku-mirror-master-2/
It is focused around token generation, and is designed to function independent of Riku. My average CMC is higher than yours, but I have 36 lands and 10 other mana sources.
I use a template that ensures I have sufficient mana, targeted removal, mass removal, card draw, and card advantage.
For comparison, a competitive deck would have a land count, mana source count, and CMC curve more like this:
http://tappedout.net/mtg-decks/yisan-bard-of-the-eighth-verse/
On a side note, Boros is crap. The two weakest colours combined to form the epitome of weak.
I personally prefer Reflecting Pool and Meteor Crater over Exotic Orchard. The Orchard isn't a bad card, but I feel that I have more control over colours with the Pool and Crater, even if they may be less reliable sources of mana. I have Exotic Orchard in one of my 5 colour decks, and my Narset deck.
The ABU dual flex isn't very helpful, not everyone can afford to include them. If you think ABU duals are standard for Commander, YOU need to get real.
I can definitely get behind Strip Mine and Volrath's Stronghold though, excellent lands.