Unctus, Grand Metatect 2
A downgrade on Grand Architect without shedding any of that narrowness. There are places I might play this but three is generally quite the top end spot for those sorts of places so outside of EDH and those spacious 100 card decks I cannot see a place for this in singleton. The artifact decks don't love colour intense cards either so this isn't even competing well with cards like Sai, let alone Nettlecyst or Etched Champion.
Norn's Wellspring 2
A cheap means to cash in on dead dorks. Every pair of dead'ns gives a Preordain. Cool. Four dead dorks and this has paid for itself comfortably. Sadly four dead dorks is a thing for aggro decks to do and they are not into skipping the option to apply pressure. This might well just come out too late for them. I like that it works with tokens but all I prefer my value to come in proactive or more reliable ways. The price here is right but the suitability is off. I do want to have a little play with this but I don't really feel like I need to test it... I much prefer Transmogrants Crown to this as it does something on top of the value, despite not being quite so good at the value side of things.
Blade of Shared Souls 1
While this is a very cool design being interesting and unique, it is still a Clone. Clones are polar cards that don't play all that well, and those that only target your own creatures are typically also just bad in addition to these other issues.
Archfiend of the Dross 2
Cards with the word Dross in the title have always been synonymous with shit. Dross Crocodile anyone? This is a reworked Abyssal Persecutor. One in which you lose trample, gain a draining passive, and gain a time limit on when you need the card gone by. At least you can win with Archfiend in play but it is quite a scary times card. No trample means you will need a healthy amount of removal, not just to hit their blockers but also to trigger the drain. You have three attacks with this before it turns on you and ends your life. Yes, you can sac or kill if yourself if it isn't getting the job done but this requires cards and increases the risks. I don't see this as much better than Persecutor and that card hasn't been exciting in cube for ages. Just big stats do not excite. Risks and hoops to jump through reduce a lack of excitement to strong dislike. Sometimes the drain will be too much for people, but not often enough to overall make this at all good. I was pretty wrong about Sheoldred which does have some similarities to this, being a 4 drop with stats, a drain passive, and no real other value. The thing about Sheoldred is that the power level is a lot higher and it comes with no baggage at all, it is all upside with Sheoldred. All in all Archfiend fails to break the Dross curse.
Graaz, Untoppable Juggernaut 2
I see this more as a take on Craterhoof Behemoth than anything else. This is a card you flop and alpha strike with and not a card you deploy and win with over a couple of turns. Not many decks have lots of weenies but want a big artifact instead of a green dork. Perhaps some Mycosinth Golem affinity brew. Sounds like a lot of fun but also sounds like a weak version of other decks. Overall there is just not much demand for what this offers.
Melira, the Living Cure 6
This is a whole lot of Watchwolf! In cube I expect the poison slowing to be irrelevant however the other ability is also good. A very strong Dauntless Bodyguard style card. This is very much one of those cards that is comfortably there on power level but is not just a gold card for which there is less space, but also the wrong kind of gold card. I have found you want that top end pull rather than the low mana value deck padding, even if it is premium quality padding! This will play well in cubes across the board, it will just not see enough play or impact drafts enough positively to be a card I want to run.
Black Sun's Twilight 7
Curious. As removal this is shockingly bad always costing you tempo to use and being clunky and slow. As a big value blowout play it is quite juicy late on. It reminds me of the various 5 mana saga removal spells; Elspeth Conquers Death and The Eldest Reborn. It is a bit faster acting that the sagas but costs a little more. It can also be used earlier in the game if needed. As a six drop this should be utterly game winning, even just getting back something like a Gonti or three drop should still be a devastating swing. Instant is scary too allowing you to kill their thing at EoT and attack with your thing right away. I think this has a shot in cube, I do not love the card but it is the right sort of thing. Usable early, lots of options, direct, but also some powerful scaling into the late game. I don't love it, I see myself using it a lot at two mana to kill one drops and that kind of general sad inefficiency. Bad as that will feel at the time a card that can stop you dying early and does a good job of winning late is hard to pass up.
Vindictive Flamestoker 7
Nothing wrong with this. A 1/2 for R that cashes in for 4 cards later down the line. This is bad in the face of mass removal as it will not do all that much as a body only to die before you can use it. Against spot removal it is great just thanks to being a one drop meaning you are likely never losing tempo. Six oil counters is a lot to get but you are perfectly happy firing this off for four mana or so, really, whenever you run out of gas the price for four cards will be right and you should be able to afford it. This feels like a Bomat Courier that is easier to draw cards with and generally a little safer. It isn't a bomb by any means and may just be weaker than a Phyrexian Dragon Engine as a refuel card. One drops with draw 4 on them absolutely excite however and so this is getting every chance to prove itself in cube. If it were not for mass removal effects this card would be straight up outstanding but the risk is obviosuly getting it killed incidentally for free while you charge it up and this costing you a card rather than gaining you three as you had hoped..
Encroaching Mycosinth 1
This is a lot to pay for a do nothing. Obviously a build around only card but seemingly not a great one even at that.
Bloated Contaminator 6
Dangerous card that is clearly quite a big push for toxic green decks in standard. I presume this can proliferate the first toxic counter making it toxic 2. Even without the toxic a 3 mana 4/4 trample that proliefrates on combat damage is quite exciting. Lots of counters in cube that we want to multiply! This is a bit vanilla and really needs support to work that proliferate angle. Ultimately while this is very powerful I think it isn't the kind of card to last in cube. Not without a desire to force certain synergies at least, in which case this is a useful leverage tool.
Monument to Perfection 2
Fun card with one of those achievements to unlock but not a powerful card, even if the spheres and locuses prove powerful. EDH can likely do cool things with this.
Ria Ivor, Bane of Bladehold 2
Too situational and narrow. Certainly powerful with a terrifying ceiling but not a good fit for cube.
The Monumental Facade 3
One of those really cool enabler cards that will have some lovely synergies and likely crop up in loads of standard decks. For cubes however this is not going to be working for enough cards to get a look in. A build around only.
One turn of fixing and a land that is always ready to use is already not that bad of a land. To then also have the ability to throw out toxic tokens is pretty impressive. It is cheaper to use than Castle Ardenvale too! Yes, they can't block so it is offense only but even so, this is a very efficient land all round with fairly little drawback. I suspect it is a little too slow for cube but it still needs testing due to that high looking power level.