Simplicity Cube

I've created the Simplicity Cube, a cube for beginning players using some ideas from existing designs (see bottom). Similar to the 180 Beginner Cube, I want this to work with 4 player drafting and also be useful for creating quick mono-color decks for teaching a new players, including kids.

Use mostly simple, elegant cards with short rules text. Lots of reading is tiring for new players.
Non-evergreen keywords are almost completely absent.
No counters (+1/+1 or otherwise) placed on cards.
Token producers included sparingly, limited to a few common types.
No library searching or shuffling.
Aggro and control supported in every color.
Comprised mostly of cheap cards.

I used card selection criteria similar to 180 Beginner Cube, while attempting to select cards with some of The Elegant Cube's ideals in mind. The criteria above eliminate a lot of cards, but I still want to avoid a cube that's too vanilla. Complexity on some cards is fine as long as it carries its weight in terms of fun and interesting play.

I welcome feedback! I'll list some known issues and meandering thoughts in the second post.

Sources of Inspiration:
The Elegant Cube
180 Beginner Cube
Core Resonance Basic
Low Power Core Set
Building the Noob Cube
Some issues that I've noticed already. I'm sure other people can spot various others that I haven't noticed yet.

1) Black is more wordy than the other colors, and the graveyard theme got more extensive than initially intended. I like the way the grave theme looks in combination with the life stuff, the aggro cards, and some of green's cards that work fine on their own. I'm not sure what to add to black if I remove some of the graveyard interaction.
2) I can't think of a satisfying way to deal with nonbasic lands in the draft. Maybe I should just give everybody a couple dual lands of any color combination they want.
3) The average mana costs are a bit low. I think I need a few more cards in the 4-6 cmc range. While there are lots of cards in that range that I love (I enjoy complexity), it's harder to find ones that seem to be exciting, good fits for this particular cube.
4) White seems too simple. I need to figure out something else to add to it. It's the only color with two vanilla creatures, and it has a lack of choices on the cards. Minor note: I need to replace either Selfless Spirit or Selfless Savior since they are redundant. There are a few other redundancies that I haven't caught yet.
5) When I test drafted this with 4 total players, either the bots are weird or I'm getting too many playable cards when I do 5 packs of 9 cards. Maybe this would be better with less cards in a 4 player draft.
6) The creature to non-creature spell ratio seems skewed a bit too much toward creatures.

I wasn't going to include tokens, but then I talked myself into it. Cards like Attended Knight and Deathbloom Thallid aren't too hard to figure out. I only included soldier, goblin, saproling, and zombie tokens. The only repeatable effect is Null Caller, which also uses graveyard as a resource and provides a mana sink. I am avoiding cards like Avenger of Zendikar and Pentavus that create more complicated token situations. It's hard to find a green token type that has 2-3 nice cards for this cube, because green makes so many types of tokens. I don't really want to have Elephant Guide making a 3/3 elephant while Brindle Shoat makes a 3/3 Boar token and Crested Herdcaller makes a 3/3 Dinosaur, because I want the cube to show that some types of tokens are produced by multiple cards.

I had a few +1/+1 counters cards in at first: Ajani's Pridemate, Bloodthirsty Aerialist, and Champion of the Parish. I'm open to including a few as long as they are fairly easy to understand and keep track of during a game. At first I thought Ajani's Pridemate was going to be important, because new players like life gain and it's one of the rare decent payoffs. Eventually I trimmed that since there weren't many +1/+1 counter cards that I felt were needed, and it's cleaner to not have to worry about them at all. I trimmed back on the life gain stuff after getting a little too into it.

I believe the only non-evergreen keywords in the first version are Battle Cry on Signal Pest and Morbid on Tragic Slip. Those could both go, but I like the flavor and resonance of Tragic Slip, while Signal Pest is handy as a colorless aggro one drop.

Of the evergreen keywords, I left out regenerate and defender. I thought about leaving out hexproof and/or indestructible, but they're important on combat tricks.

It's striking how much different this cube is from my first cube, in which I tried to maximize synergy.
Nice! Tried out a draft:

WU Fliers

I feel like you have a pretty wide power band that by itself is not a problem. It doesn't seem like a distribution peaking in the middle of the curve with a few outliers, but it seems to have two peaks, which means a lot of the cards end up not really worth maindecking.

More concretely, when I can run Voracious Greatshark and Mind Control, vanillas like Coral Merfolk and Ironclad Korvold are easy to cut, and since there is a focus on good-stuff rather than archetypes, the roles of those two cards are really niche.

Since the high power cards are mostly answers, this isn't a terribly warping issue for the environment, but I feel like you could increase the floor of the power band and still maintain your goals.

Replacing for example:


Of course, if the idea is to have some card that are actually bad ( then forget about what I said :D


Ecstatic Orb
I spot a Squall Drifter in that deck. That's a snow creature. I think snow is a pretty advanced mechanic, as it's sort of a mana supertype as well. If someone asks you "what does it mean that this is a snow creature instead of a normal creature?" and you have to answer "nothing, just ignore it", it feels like that's against the spirit of this cube. A good alternative is Niblis of the Urn.

Also, flying is really intuitive, but if you're looking for something with reminder text, these actually exist!


It's from the Welcome Deck 2017.

Also, I do agree that entirely vanilla creatures should at least be worth it for their stats, otherwise they're just the first cut you make and don't add to the draft environment at all. Elite Vanguard is great, Ironclad Krovod is just bad.

PS Keep an eye on the curve. I think your white section would benefit from another three drop instead of a four drop, for example.
Squall Drifter looks very similar to Niblis of the Urn but plays very differently. Squall Drifter is a Suntail Hawk that pecks for 1 until the big dudes are deployed by the opponent, then it's Icy Manipulator. Niblis of the Urn is much more aggressive, as you can't use it for defense at all, so there's not much choice but to attack with it - and it attacks _way_ better than Squall Drifter does.

Both are good for this cube, I think. Depend on whether you want an offensive creature or a defensive one.

Agree the snow supertype might be a bit confusing and inelegant, but it's not the end of the world. I'm getting Future Sight feelings.
Thanks for the feedback and the drafts!

I updated a bunch of cards to smooth out the power curve, and I also attended a bit to the mana curves. I think this has helped to make it less of a bimodal power distribution. I do want a difference in power levels, but not in a way that leaves a bunch of obvious chaff at the bottom.

White has a bit of blink now (3 cards), which included adding Master Splicer Wing Splicer. I eliminated the sole Zombie token card, Null Caller, at the same time, so it's still only four types of tokens. I messed around with most of the big creatures, which I still find challenging to select for this cube. Black has a bit more reanimation, including Living Death. Black 5 and 6 drops are a problem for me. I could add Bloodgift Demon, but then I wouldn't really want the flying Gravewaker in the 6 slot. I threw in Champion of Dusk. Aggressive black 2 drops are also challenging. Gifted Aetherborn replaced Royal Assassin to help the curve and help aggro. I changed out Mind Control for Confiscate. Lots of the weak creatures have been upgraded. I took out three of the creature auras. I reluctantly added Glory-Bound Initiate, which added the exert keyword. It's not a hard one to understand, and I like the card quite a bit. I added Relentless Assault to red. This is probably considered a bad card, but it's a simple to understand effect that I've always liked, and this cube offers a few fun tricks with it. I got green away from self mill. Some bad artifact creatures are removed. I don't like the triland setup, so I added seven Evolving Wilds instead, which gives four players a bit of light competition for generic mana fixing. I drafted a Grixis deck in the simulator, and the bots gave me 6 of the trilands, 5 of which fit my colors. I suppose that's approximately what would happen if I drafted this with new players.

The mana curve looks okay to me at this point. If it's obviously off, then I'd be interested to know where it looks messed up so I can adjust.

I'm stealing so many cards from The Elegant Cube that it probably seems like I took that cube and cut it in half, but I swear I didn't do that.
I like the new iteration a lot!

(But let me nitpick a bit more!)

I didn't play much DOM draft to remember how good it is, but Charge seems a bit redundant with Glorious Anthem, and the tokens deck doesn't look like it needs more help.

White and blue have a ton of fliers. Green has some flier hate, which helps, but since the red removal is sparse, it's something to keep an eye on.

If you want to play online and test some decks, let me know.
Nitpicking is welcomed. I did some more nitpicking of my own on the list. I can't leave things alone.

I did some draft simulations with four packs of 9 or 10 instead of five packs of 9, and it seems to work pretty well. Reading less cards and spending less time making cuts keeps things simpler.

Finding interesting non-creature spells is a challenge overall. After a while it's hard to find effects in white / red / black that aren't just more removal spells, or more draw and counter spells for blue.

Testing some decks would be awesome. I'll message you and see if we can figure something out.
I spot a Squall Drifter in that deck. That's a snow creature. I think snow is a pretty advanced mechanic, as it's sort of a mana supertype as well. If someone asks you "what does it mean that this is a snow creature instead of a normal creature?" and you have to answer "nothing, just ignore it", it feels like that's against the spirit of this cube. A good alternative is Niblis of the Urn.

So, I removed Squall Drifter, since I agree that snow is a wart on an otherwise clean design. I replaced it with Gideon's Lawkeeper in a batch of changes. Later, I added Saddled Rimestag without realizing it was another snow creature. I've found a lot of annoying little design blemishes on various cards during this exercise.
Been drafting some decks. Cube Cobra bots are too biased, so I keep getting the same cards I consider good and they don't.

As an aside, with all the deathtouch, I think some thing like Lavamancer's Skill could be an interesting.

Good idea. I was hoping to get a few auras in the cube, and the initial batch got mostly removed since they were weak. For now I added Power of Fire in place of Cunning Sparkmage. Although I do like Cunning Sparkmage as a card. He might go back in if I shuffle the red 2 and 3 drops around a bit.

I was wishing one or two of those creatures didn't have deathtouch. There are seven deathtouch cards at the moment to only one creature with menace, for example.

Are the CubeTutor bots any better? I could put a copy of the cube over there. Right now I just have a list of potentially useful cards on CubeTutor to save me time on future updates:
Thanks to japahn for an invaluable testing and feedback session. Also thanks to the others that drafted the cube on CubeCobra.



Vampire Nighthawk and Crystal Ball are too strong in favor of control decks. I should have known better. I reduced the blue fliers by one creature, added a utility burn spell to red which seemed to need it, improved a weak black removal spell by a mana, and switched Pull From Tomorrow to Negate to favor blue aggro a bit over blue control (cheap counterspell vs sweepers).

Picking wrath spells is painful. One point of feedback is that 4 mana wraths are too strong for this cube's aggro. Probably true. I'm attached to Day of Judgment, one of the game's most resonant three word spells. It could be Planar Cleansing or End Hostilities, but I am inclined to keep Day of Judgment as a bomb at the top of the power curve so that particular card design can stay in place. Languish became Crux of Fate, in spite of the dragons matter junk (yuck). If I ever get to play this cube with players who learn enough to care about the power level of spells, I'll switch it.

One of my goals has been to include a bunch of widely recognized cards in the cube, which can help a new player learn some of the game's lore, or it can make things smoother for a novice player who has already seen some cards. I could change Shivan Dragon to Flameblast Dragon or Conquering Manticore to make it better, but I'm hoping Shivan Dragon is good enough so I can include that card from Alpha and a bunch of core sets. There are more cards that I could swap in to increase that sort of recognition, like Giant Spider over Grazing Whiptail. There are some trade-offs between balancing the cube and sticking to my simplicity / resonance goals. I go back and forth with myself on some of those choices.
Regarding the use of 7 Evolving Wilds:
(also Prismatic Lens, Mana Geode, and a few green fixers)

It was mentioned that the cube might need more fixing, such as more Evolving Wilds. That might be true, but for now it's hard to figure that out, since the CubeCobra bots pick them really highly. It always seems like there's no mana fixing in the cube for that reason. The feel of the mana was different on TappedOut than it was on CubeCobra, because those bots actually let us have some Evolving Wilds. I think I would need to test this with four humans to get a better feel for it, though.

Here's my general thinking on the mana.

1) Evolving Wilds are nice, because they make any of the lands available to any two color deck, unlike dual/trilands.

2) Limiting the amount forces players to compete for those instead of expecting them to wheel.

3) Limiting the amount favors two color decks over 4/5 color decks, since 2 color decks don't need as many fixing lands. Good stuff decks with all the fixing could otherwise be a problem with everything being 5 color fixing.

4) With smaller packs ( four packs of 10 seems to work well), I'd like to avoid having too many packs that are missing two colors. Having a lower percentage of lands and artifacts helps that.

5) Less Evolving Wilds are wasted in a draft as compared to dual/tri-lands that sometimes end up with a player who's not playing the right colors.

6) I'd use Prismatic Vista instead if it was cheap, probably. Or maybe a mix of both.

I'm totally open to the possibility that I might need to increase the number from 7 to, say, 10 out of 180 cards. I don't think it would be desirable to dial it all the way to 10-15% of the card pool.
Goals of latest changes:

Further improve aggro relative to mid-range
Add white blink targets
Improve incentives to draft green
Add tribal relevance for zombies and elves

Gideon's Lawkeeper -> Dauntless Bodyguard
Impassioned Orator -> Cavalry Drillmaster
Fencing Ace -> Indomitable Will
Territorial Hammerskull -> Banisher Priest
Take Vengeance -> Savannah Sage
Star-Crowned Stag -> Inspiring Captain

I'm back and forth between Savannah Sage and Arashin Cleric. Either for control decks to survive without having to add too many white removal spells, while also being a blink target, while also not being too stifling. A 3 toughness blocker is significant with all the 2 power creatures, but I like a 2/2 body with less life gain.

Indomitable Will is a little sketchy / bad, but the concept is that white has a ton of 1 toughness creatures that could benefit from this effect. A 2/1 that becomes 3/3 becomes a much more relevant body in this environment. The ability to use it as a combat trick makes it somewhat interesting. I wish I had a slightly more powerful white aura option, such as a one mana version of Indomitable Will or Brilliant Halo. I also think a +2/+2 aura for one mana would be appropriate.

White has plenty more go-wide cards that I could run, such as Benalish Marshal, Kongming, "Sleeping Dragon", Rhox Veteran, and Pianna, Nomad Captain. The latter two are interesting with Relentless Assault.

No changes in blue, interestingly. It seems to be in good shape.

Angler Turtle might be too strong, but it's a simple, neat card, and we'll see how it looks after testing the improvements to aggro. Murder of Crows is quite good and could be simplified down to Air Elemental.

Moment of Craving -> Last Gasp
Deathbloom Thallid -> Cursed Minotaur
Scrapheap Scrounger -> Graveyard Marshal
Falkenrath Noble -> Keening Banshee
Eviscerate -> Liliana's Mastery

Falkenrath Noble fit the aristocrats deck, but it isn't strong or necessary. Keening Banshee adds a juicy blink target, which black didn't have.
Last Gasp replaced one of the -2/-2 removal cards to improve removal variety a bit. I'd love to add Diabolic Edict instead (so simple!) but it's probably not good enough with all these little creatures running around.

I like Deathbloom Thallid, but I don't like that it creates a Saproling. Zombie tokens are the resonant token in black, so Graveyard Marshal and Liliana's Mastery went in.

The first time I made a cube, I had too many 1/1 creatures with nerdy abilities, yet this time around I find that black doesn't have any non-aggressive bodies. Maybe that's alright.

For better or worse, black has the most synergy within its color at the expense of having more text to read on the creatures. It's too bad the power levels for some of the simpler cards are bad; for example, I wish I had a Reassembling Skeleton with the stats of Gutterbones, and Doomed Dissenter would be a pretty nice card if it was a 2/1 or a 2/2 instead of a 1/1. Fortunately, black's non-creature spells are mostly not too wordy.

The 5+ drops are tricky in black. Other cards under consideration include Underworld Sentinel, Bloodgift Demon, and Harvester of Souls. I don't want all of them to fly, or for all of them to draw cards. Black lacks a really splashy creature to properly pay off Zombify, but I'm letting that go for now. A player so inclined can look to the other colors' big creatures (see green, below).

Spikeshot Elder -> Goblin Guide
Beetleback Chief -> Ball Lightning
Engulfing Eruption -> Thunderbolt

I really wish I had some more one drops to choose from in red. Like, a clean 2/1 for one doesn't seem like too much to ask. In practice I might run Zurgo Bellstriker or Firedrinker Satyr since they're cheaper, but in general I'm dissatisfied with the options available. Losing Spikeshot Elder's fun tricks hurts a bit, but red aggro can use a 2 power card in that slot.

Thunderbolt is in because I wanted to give red aggro some more reach. It's also another instant speed prowess trigger, which Engulfing Eruption is not. I would really like to include Lightning Axe, for reasons of ubiquity in core sets and simplicity, specifically the clean M10 version with "Catch!" flavor text, but at 5 mana it's not good enough. It should have been a 3 mana card that does 4 damage. I could do Flames of the Blood Hand or Pulse of the Forge, but Thunderbolt is more interesting and appropriate and clean. It's a pity that it doesn't have the newer bullet point text styling.

Red had three cards producing multiple goblin tokens, so I removed one. Keeping Siege-Gang Commander is a little sketchy since it's quite powerful, but it's also a fun and interesting card that draws people to red in the draft. Maybe that will go away later and Beetleback Chief can come back. At any rate, Ball Lightning is a much more aggressive card than the mid-rangy Beetleback Chief. I think a triple red can replace a 4 drop, sort of.

Impetuous Devils fits the mechanics of the cube a little better than Ball Lightning, but on the basis of simplicity and history and resonance, I changed my mind and went with the cleaner card.

Also under consideration: Goblin Oriflamme could replace Power of Fire to further buff aggro decks. Some of them, at least.

Frilled Sandwalla -> Rancor
Darkthicket Wolf -> Saddled Rimestag
Deeproot Warrior -> Kalonian Tusker
Atzocan Archer -> Hooded Brawler
Grazing Whiptail -> Dwynen, Gilt-Leaf Daen
Silverback Shaman -> Somberwald Stag
Keeper of Fables -> Ant Queen
Overcome -> Overrun
Treeshaker Chimera -> End-Raze Forerunners

Green gets the biggest list of changes.

Hopefully the addition of Rancor provides motivation to be aggressive in this color, along with some of the other improvements to the quality of the 2-3 mana beaters.

The selection of beginner-friendly aggressive green one drops is failing pretty hard:

I reversed course and put a snow creature in since Saddled Rimestag is otherwise just too nice and simple and good.

It's a shame to remove Atzocan Archer, but I really like Hooded Brawler as an attacker. It is now the second creature with exert (Glory-Bound Initiate. I like exert. Prior to that switch, I had five three drops in green, and four of them were mid-rangy enters-the-battlefield creatures. I might consider adding the archer back in and removing Regrowth, because I like all of the green three drops. I wouldn't mind having Steel Leaf Champion in there, but I'd have to cut something I like to make it fit. Perhaps Llanowar Visionary or Eternal Witness should go away instead of Atzocan Archer, but I am attached to those cards.

I like the four drops as well, but I upgraded Grazing Whiptail to Dwynen, Gilf-Leaf Daen who has the same stats. I wish it didn't have the extra text about life gain - without that junk, her card would be short and sweet.

The green five drops get a significant upgrade. Adding insect tokens is annoying but hopefully worth it. Hopefully they provide something besides Carnage Tyrant to entice people to draft green.

I'm uncertain about End-Raze Forerunners, because it's perhaps too much, but that gives ramp a fun target to shoot for, and it's also a nice, big reanimation target for Zombify. I estimate that it's closer to the mark than Treeshaker Chimera.

Filigree Familiar -> Pierce Strider
Vulshok Battlegear -> Scrapheap Scrounger

Filigree Familiar gums up the board and prolongs games for mid-range, while Pierce Strider provides reach, so that goes along with some of the other changes.

Vulshok Battlegear is too mana intensive.

*I'm classifying Scrapheap Scrounger as colorless, but I'm not sure if it will register as an option for aggro drafters in the non-black colors.

I might add Coldsteel Heart.

I still would prefer untapped lands for the aggro decks, but for now it's still Evolving Wilds. In a paper draft, I think I'd simply let people trade in Evolving Wilds for check lands and such if they want them.
Just drafted a fun looking Mardu control list!
Some feedback off the cuff, but i plan to draft more and get a deeper understanding of the format, i LOVE beginner-oriented cubes:
-i checked some of the analysis options in cubecobra and i like your CMC curve.
-the density of scry effects is GREAT. i would recommend looking for lots of “draw a card” riders as well. drawing cards just feels good!
-the custom fixing land is cool. what’s your reasoning behind running exactly 7 in the list?
-also question the omission of gold cards. there are lots of simple gold cards that telegraph a theme idea to drafters. even a guildmage or something like Electrolyze would be a benefit imo.
-finally regarding your latest post, i wouldn’t worry too much about complicating the manabase. aggro will still be a thing without untapped lands. it will just adapt to the environment by using fewer colors or starting on turn 2.

anyway, greatly enjoyed the draft and thanks for making a great entryway to Cube for new players! keep at it!
Thanks a bunch for the drafts and comments.

I swapped the image to the custom wish / untapped land just for the heck of it. Seven was a number I pulled out of nowhere because it was one less than two wilds per player, which creates competition for those lands. Maybe I need more. What number would you estimate to be appropriate? As I think about this, only 160 cards get drafted, so the average per draft is 6.2 wilds, or about 1.5 per player. That does seem a bit low. A total of 9 would result in 2 per player on average.

I gave a bit of thought to gold cards when I first sketched this out in my head. I left them out for a few reasons: focus on mono-colored cards to make drafting and deck building easier; maximize the density of mono-colored cards found in the 10 card packs so you can pick your colors more of the time and have more playable cards; a few guilds don't have simple cards that I'm satisfied with; many of the simple cards like Mortify are just removal spells, and I don't want to add a bunch of efficient removal.

So if I went gold, would it be 10 or 20 gold cards?
1) 10 gold cards: having just one gold card might send a stronger signal than I want, indicating that here is the one true way to play the guild colors. But, some cards lend themselves to multiple strategies in a nice way. If I can find suitable cards for all or most of the guilds, that might be good.
2) 20 gold cards: this probably also leads me to increase the number of fixing lands to make it easy to splash for a 3rd color. This would enable me to deliberately pick gold cards that lead the drafter to different strategies for the color pair. That would improve the variety of decks while also making the draft more complicated.

Option 2 leads me to ponder the ideal size for the cube. I picked 180 because it's 45 x 4, but since I've been test drafting it with just 40 card pools, the number 180 is not a requirement. If I added 20 guild cards, that gets the cube to 200 cards. I'd want enough fixing lands to expect a little more than two per player in the draft (guessing). If I added 5 more and got to 12 lands, and maybe another mana rock or two, that's more like 207 cards, resulting in an expectation of about 9 lands to go between four players in each draft. That's a little interesting, because with 200+ cards, it would now be possible to draft with 5 players with 40 card pools. It also leaves 22% of the cube unused. That many missing cards might be a little rough on some of the possible archetypes - not sure. It's also an option to cut a colored card or two from each color if I add gold. Cutting five mono cards and adding 10 gold and 5 land would make it a 190 card cube, so that wouldn't be quite as big of a change.

I hunted for simple cards from each guild. I did not consider split cards or hybrid cards, because I suspect that they would be unable to offer enough to make me overlook their added elements of complexity.
I've added those to my overall card pool of simple cards:

Thinking of a 10 gold card setup (one per guild), here's a shot at selecting those cards.

Azorious: Maybe Spell Queller: I'm not sure I like this power level, but unlike some of the other UW possibilities, this doesn't signal that UW is only control or only fliers.

Dimir: Tomebound Lich fits into some different tempo or aggro/control deck ideas.

Rakdos: Judith, the Scourge Diva can be an aggro lord or an aristocrats type of card.

Gruul: ??? My options here seem to mostly signal midrange / ramp in RG. I'd like an option better than Raging Regisaur, but I don't really know where to go with this one. This is partly because I don't know exactly what I want these colors to be able to do.

Selesnya: ??? These colors allow some things like control, blink (which is basically midrange goodstuff), and go wide. Maybe Dauntless Escort or Saffi Eriksdotter would work here.

Orzhov: ??? Nothing jumps out at me. Some of the typical Orzhov cards with life gain / taxation themes would send false signals about a life gain theme that isn't really supported. As I said above, I'd rather avoid making these cards a bunch of efficient removal, but Vindicate is about as simple and elegant as a card can be, even if it doesn't exactly help you figure out what to do with this color combination.

Golgari: Skull Prophet: works for ramp, allows some graveyard stuff, and 3/1 for 2 mana would work with an aggro deck that was also picking the cheap black creatures. Actually, I think I like the way this creature would be able to switch from aggression early to mining for value later when a 3/1 body isn't strong enough anymore.

Izzet: Stormchaser Mage or Izzet Charm are both spells matter cards, but they at least fit a spectrum of those deck styles. Electrolyze in this cube feels a little too brutal since there are a lot of one toughness creatures.

Simic: ??? It seems like this card should specifically help a UG tempo deck, which I believe could use a little more help, without specifically only working with that deck style. UG already does pretty well at building control and ramp decks. Mystic Snake or Frilled Mystic would be fine in any of those, right? Bounding Krasis is a bit interesting, or maybe Maraleaf Pixie.

Boros: This card should at least support more than one type of aggressive deck. Maybe Skyknight Vanguard? I like Heroic Reinforcements somewhat, but it's almost entirely a go wide card. It feels uninspiring to run Lightning Helix, because similar to Vindicate (or Putrefy or Electrolyze or Terminate) it doesn't light the way to an interesting deck idea. It seems like this should be an easier guild to find one simple gold card.

So here's a draft of a potential 10 card gold section. I'll have to think about whether this is what's best for the cube or not, but it seems worth a look.

Edit: swapped Boros Charm in for Skyknight Vanguard
Here's a quick run at a possible 20 card gold section. Having two of each guild causes me to select them a little differently. I find Gruul, Selesnya, and Orzhov to be the most difficult.

Maybe I like Boros Charm in place of Skyknight Vanguard on the 10 card gold section in the previous post.

On a note somewhat related to those Boros non-creature spells, Seeker of the Way is a card I'd like to sneak into the white section.
i think i like your 10 card gold selections the best! those are nice finds. but i think it’s limiting your options if you ignore hybrid cards.
here are some other options you might look at, especially for going to 20, though they play a little fast and loose with the Simplicity rules...

Again, i think your first post of 10 golds is super strong.
Thanks for having a look. I also like the 10 card list better than any 20 card list that I can come up with right now.

I'd run a guild card with a bit of extra complexity (hybrid, split, keywords, etc) if the design fit nicely enough into one of the more challenging guilds.

Edric could work. I looked at him and he'd be pretty strong, but possibly appropriate. I also like Soul Manipulation and Prophetic Bolt.

I'm adding Radha, Heart of Keld. I glossed over that card before, but she might be a more interesting choice than Raging Regisaur.

I also switched out a few others.
Raging Regisaur -> Radha, Heart of Keld
Power of Fire -> Uncaged Fury
Savannah Sage -> Seeker of the Way
Kalonian Tusker -> Noose Constrictor
good changes!
a couple things i’m noticing as i continue to draft:
-removal is AWESOME, i can’t stop myself from picking it and always end up in control! but the control decks look fun!
-there are a lot of sac and discard outlets, but not a lot of ways to benefit from them... a few, but i want more! i’ll suggest a few below.
-you have a 1 mana red instant, i forget the name. that adds +3/+2. may i recommend Titan’s Strength instead? +3/+1 scry 1

here are some suggestions for discard and sac payoffs. i tried to keep them mostly simple.

Really enjoying drafting this cube!
EDIT: trying to come up with these discard/sac payoffs with no flashback etc allowed really brings to light how hard it must have been to put this cube together!
Infuriate -> Titan's Strength
Frenzied Goblin -> Tuktuk the Explorer
Noose Constrictor -> Mother Bear
End-Raze Forerunners -> Soul of Zendikar

Removed to reduce cube to 190 cards:
Niblis of the Urn
Turn to Frog
Champion of Dusk
Tormenting Voice
Meteor Golem

As I take a closer look at the sacrifice and discard outlets, here are my thoughts:

Black: already in decent shape to utilize discard/sacrifice outlets. I really like Reassembling Skeleton's design, but as a 1/1 it's weak. I've strongly considered Blood Artist. One of the reasons I don't have that is I'm trying to mostly avoid cards that are only good in a specialized deck. The way it is set up now, I think it's tough to completely train wreck a draft as long as you try to draft a two color deck since most cards can go into a regular deck that attacks with its creatures.

Green: Noose Constrictor was an attempt to get more interesting than Kalonian Tusker, but it sends a false signal that green can't pay off. Rather than fixing that, it makes sense to simply replace it with Mother Bear as a graveyard bonus for Evolutionary Leap.

I also put in Soul of Zendikar over End-Raze Forerunners. I have concerns about the latter's power level, and Soul of Zendikar provides a mana sink to still support ramp but also is a graveyard payoff. Maybe that's an overall improvement despite adding a yet another token type. Zombify takes a hit as a result.

Goblin Bombardment is red's only sacrifice outlet, an red has some things that go well with it (tokens, Act of Treason, Impetuous Devils). With the various one toughness creatures in the cube, it's pretty decent on its own, and it is already setup to work well with black. Having said that, Tuktuk the Explorer probably adds more to the cube than Frenzied Goblin. That changes the type of aggro one would play in some situations, but Tuktuk's version of aggro probably stands a better chance of succeeding.

Red discard enablers could use something. I trimmed Tormenting Voice to get down to 30 of each color after adding the 10 gold cards. Maybe that card was fine, but I dumped it because I knew the discard payoffs weren't there and it feels like deck filler.

Squee is very tempting since he pays off both discard and sacrifice. He's very simple and unique. I think Tutuk will play a little better overall if it's between the two. As a discard payoff, Squee is mainly a snowballing card drawing engine for the loot/rummage effects in red and blue.

Blue: these discard effects are loot effects that don't require synergy to be viable, and they offer choices to the players as is, so I think the game play can work with the way it's currently setup. Wonder is interesting but a lot of blue creatures already fly. I think blue can stay as is with its looting and supporting UB graveyard plans.

I've messed with the mix of removal a bunch of times, but I just don't have a good feel for what's best. I'm completely open minded about trimming it back or replacing some with less powerful stuff. This is a really easy pitfall in designing this particular cube, because nice removal spells always pop up when I'm looking for simple cards to fill a slot.
I REALLY like the addition of the Souls!
Drafted a few more decks... I’m trying to keep track of my early picks, and it seems like i keep getting a wrath or Resto or Ewit or Arena, just some nutty good card early on, that puts me on the WBx control path every time. At this point it could be player bias on my part, but for whatever reason the control cards in this cube just speak REALLY LOUDLY to me compared to the aggro stuff. And there’s some good aggro stuff in here for sure!
The control stuff might just be better than the rest. It's hard for me to be objective about that, because I've been deliberately test drafting different types of decks. If you have suggestions for appealing cards that would speak to peoples' more aggressive instincts, fire away.

The power level of Restoration Angel bothers me a bit. I might need to switch her out for Glimmerpoint Stag, Stonecloaker, or maybe Kor Skyfisher.

I did a couple of 2 human + 2 bot drafts today. One game featured a Shivan Dragon against an aggressive white board, and the dragon wasn't quite as much as my opponent should have gotten for 6 mana. I might have to upgrade that card. Some possible replacements:

Another game had Uncaged Fury and Charging Monstrosaur for what should have been a dramatic finish. A misplay meant my opponent didn't realize he had a come from behind win on the board. In any case, it would be nice if the berserkers concept could be a little more present in this cube. One issue is that I need a few more creatures with trample, so that might be something I address.

I only swapped in Soul of Innistrad over Gravewaker because the former is dirt cheap online. I also put Bloodgift Demon over Phyrexian Delver and Empyrean Eagle over Spell Queller for the same reason, temporarily. I put together four copies of this cube online, and that change made it cheaper.

I might get another online draft in this Thursday evening (US Central time). Feel free to PM me if you're interested in joining.
I think Conquering Manticore is a very cool card, but it lends itself most readily to aggro decks and sacrifice decks, as opposed to being a good control finisher. Shivan Dragon is probably my favorite control finisher of that list, but may i also suggest:

As far as replacements for Resto! I agree she is stupid strong in this cube and easily the best white creature. I also think she’s awesome and will miss her, but it’s just a fact that you can’t bring the rest of white to her level without adding a lot of complexity. Glimmerpoint Stag is probably the simplest swap, but I like Stonecloaker a little better.
Restoration Angel -> Glimmerpoint Stag
Shivan Dragon -> Flameblast Dragon

I like all of the dragons you mentioned. Flameblast Dragon might be too much of an auto win card, which is why I didn't put it in my list, but I do like its ability help one catch up from behind.

Stonecloaker and Glimmerpoint Stag are so much more fair than Restoration Angel. Flickerwisp has the same problem of being an efficiently costed evasive creature that has a strong blink ability on top of that. I'm tempted to remove both, but I'll leave Flickerwisp since it's also a nice aggro card.

Glimmerpoint Stag is in since it keeps the mana curve the same for now. As a bonus, now all three of the blink cards have the same "return to play at end of turn" functionality, so that's a bit less potential confusion.