0 - unplayable in 40 card singleton
1 - effectively unplayable
2 - has low tier constructed decks it might go in
3 - has mid tier constructed decks it does go in
4 - pretty powerful stuff with several potential homes, able to perform well in lower powered cubes
5 - powerful stuff that is either just too narrow or has too many superior alternatives
6 - fringe cube worthy
7 - cube worthy
8 - cube staple
9 - unpowered cube bomb
10 - powered cube bomb
Luxior, Giada's Gift 2
Devoted Druid will be getting banned at some point soon in some format or other. I like the idea of equipping up walkers and getting stuck in but it isn't really a thing you can build around . That in turn means you can't really just put this in a deck with walkers because most decks don't play that many of the card type. If you are not equipping walkers or Devoted Druid then Gift seems like utter garbage as it often does nothing and is a whole 3 mana to equip. Pretty much just a combo card.
Black Market Tycoon 2
Well, they certainly found a way to avoid stockpiling treasure for one big turn with this. Much as I like the versatility here I can't see why I would play this over the likes of Paradise Druid or Sylvan Caryatid. Or, you know, Rampant Growth... Haste would have made this a whole lot more interesting. Likely still too gold for cube but still. Standard being starved of ramp as it is probably finds a home for this. Cube will likely not. This probably needed to be mono red to see action as once you are green your ramp options rather improve. In a treasure themed deck the upkeep trigger on this becomes untenable ruling it out from getting any love there either.
Hostile Takeover 1
Cute idea but three colours and five mana to essentially do a bit of an Anger the Gods is not cutting it. Yes, you keep a dork of your own if you have one, potentially even getting a good hit in with it. And yes, you should kill the best of their dorks assuming it doesn't have more than two +1/+1 counters on it or some kind of damage prevention access. That is the good part of this card. The issue is how little this does to the rest of the board. Three damage is often not even killing midrange dorks. It is a good way to stop yourself getting swarmed, or at least it is when your three damage costs three mana. As you go up the curve and later into the game three damage just isn't putting enough of a dent in your opponents board to be exciting. When this fails to fully Wrath your opponent it is not good enough and that will absolutely happen. Perhaps as often as 20% of the time if I had to guess at a figure. Languish isn't reliable enough for cube, it costs less, is easier to cast, kills bigger things, and does so more reliably and if it isn't really good enough for cube this shouldn't be either.
Arc Splitter 1
This is quite cute. It isn't unblockable nor is it removal but it is one or the other. The removal cost isn't cheap but given that it is somewhat repeatable and at no card cost you are rarely going to turn down the option to use it if presented. I think this puts too much choice in the hands of your opponent to appeal but it is nicely cheap to play and equip and makes for an interesting set of choices for everyone.
Probably better than Shatter the Sky but it turns out white now has enough Wrath of God power level equivalent mass removal tools that it doesn't need to entertain cards like this. Technically this can outclass a Wrath but on average it will not be. Or at least, not so long as the Wrath is dealing your opponent more damage than yourself. I have certainly seen opposing Wraths that helped my board more than theirs in my time! This is strong and perfectly playable. It might be useful for some budget cubes or really large cubes but I shouldn't expect that I will need it.
Stimulus Package 1
I find this a bit confusing as both halves of the card are so weak. Four mana for a pair of 1/1s or two treasure is just not close. You really need a deck that is all about making treasure and even then, I typically want a mana more than I want a 1/1. You are hardly trading up on your treasure and can probably find a better means of cashing in. This does both support and cash in so it might make it in a themed deck but it is a little embarrassing on the power level.
Call in a Professional 5
Fine little card. A little inefficient but high utility help make up for that. Not breaking into many cubes but would perform acceptably in most.
Queza, Augur of Agonies 1
Too expensive to be worth trying to abuse and too fair on power level otherwise. The tempo here is too weak and the vulnerability is too great.
Obscura Interceptor 3
I misread this and had it down as a Regrowth and not a Remand effect. As such it is a whole lot worse than I realized. Bounce a spell on the stack rather than a card in the bin means you are no longer getting card advantage with this and it also makes it much more situational as you ideally want to play it on a big spell of your opponents. Simply put I would rather play Venser than this, his ability to bounce permanents makes him far less situational and just being the one colour further adds to his playability. Interceptor is still reasonably powerful but it is not the kind of card you are looking to play, certainly not in your cube at three colours! Original review below.
Obscura Interceptor 7.5
Well, I am going to have to put some of these three colour cards in to the cube to test to at least show some willing. This is certainly a strong contender for being powerful and well suited. This is kind of like a big Snapcaster Mage with all sorts of bells and whistles. Four mana is a lot for a value or utility card but flash eases that cost massively, as does high power and lots of options for that matter! For your four mana you get a relevant body, a Regrowth, and a loot. Some card advantage, some tempo, and some card quality. You even get some choice over your body being a 3/1 or a 4/2 which is rather significant on a flash lifelink body. You can merc a 1 power dork and stand to gain 8 or more life if you want to which is a swing by itself against the aggro decks, not to mention the must kill body and then all the cards stuff! Without the flash I would likely rule this as too clumsy and risky. With it the card seems dangerously potent. We are pretty comfortably there on power, we just need to see how much play it winds up getting. Counter based control decks have been two colours far more often than not in the more recent years of cube but perhaps cards like this can tempt people back into the more traditional classic Esper control lists in cube. Lingering Souls remains a strong pull even if the removal options no longer seem so tempting.
Obscura Ascendancy 2
Hoops! So many hoops. Don't bother with this one would be my advice. You have probably won with it before you get to five soul counters. Three 2/2 flying tokens has probably put you well in the driving seat. The issue is not with the speed of this card, nor even the power. The issue I have with this is simply how often it will be dead and how often that even when it isn't you are forced into really suboptimal lines so as to prevent this becoming dead. I will likely play around with this a little as it is quite fun but I am under no illusion that it will be able to reliably perform.
Body Launderer 3
Smells like a Hill Giant to me. It does have three relevant abilities but they are all quite bye-passable. The on death trigger can be stopped with exile effects both on it and on things in the bin. It can just fail to have targets regardless of disruption. Deathtouch and connive are nice but they are not the kind of nice that makes a Hill Giant playable. Deathtouch is less impressive on larger costlier dorks like this, not without trample as well at least. Connive is nice but this is not often going to be the one surviving in play. Body Launderer is fine. It has a fair amount going on and will generally represent some value and OK tempo. It just isn't threatening, or disruptive, or reliable, or all that impressive.