It's been a little bit since I've had the time and motivation to update this cube. As a note, I haven't tested any of these changes, so let me know your thoughts.

Similar to commander it feels like the early turns are just set up for the late game. Most games are a back and forth of fighting over Inferno Titan not playing small games of incremental value. I want to lean into that a bit more.

This cube is meant to be a quick thing that people can do during events or while waiting for people to show up to FNM. I want a lot of interaction and back and forth, but not over small things. Similar to the Dandan cube, but with bigger splashier effects.

So lets give players more tools to do splashy big games that end quickly. Hurl Through Hell, for example, lets players come back from the brink and set up for a large swing.

I also want to remove some of the cards that didn't really do much. I've noticed that pumping mana into anything that doesn't forward your board state isn't a good idea. Spending mana on mazemind tome or hypnotic grifter puts you further behind.

Specific Cards

Three Steps Ahead looks like a fun card that can impact the game in a variety of ways. Let's try that over Grifter.

Tinybones, the Pickpocket Is a much cooler way of doing the same thing that Isareth does and comes down earlier. It does trigger on damage instead of attack, which might cause issues.

Magda, the Hoardmaster and Robber of the Rich fulfill pretty similar roles. Let's try out the new card.

Wildborn Preserver always felt pretty mid. I like choices that Outcaster Trailblazer gives you. Play it as an early creature or take an early turn off to let you play an off-color spell next turn.

Trygon Predator was almost always a vanilla 2/3 flier. Let's try something new.

Dream-Thief's Bandana is a color agnostic way of providing the "on hit draw" effect. It does require a creature to connect, so this change might get reverted.

Icingdeath, Frost Tyrant is a cool card, but the equipment doesn't come up that much. This change is mostly to try something new. I want to see if Magus of the Moat just stalls games or if it's an interesting tool that players can use to skirt an opponent's big threats.

Monastery Mentor doesn't have much support in the cube.

Sunset Revelry is pretty mid most of the time. Get Lost seems like a cool removal spell that also gives the cube a tool against Glare of Subdual in a single color.

Pack Rat was kind of mid. I thought it would be cool for the player that wanted to hate-draft off color cards and not get punished, but it didn't really work out.

Soulflayer is hard to get working. Unshakable Tail seems pretty interesting and plays well with recursion.

Sea-Dasher never really did much.

Daxos of Meletis never did much and has way too much text.

Gallia of the Endless Dance was generally a pretty good aggressive play, but it did feel out of place a lot. I want to try out Bloodbraid Elf to see how cascade feels as an effect.

Knight of Autumn is a good card, but I want to try out other cards.

Hydroid Krasis doesn't play well with the cube's general theme of steal your opponents stuff.

Maybeboard

Smirking Spelljacker seems like a really cool way to stop your opponent's bomb and set up for later. I don't really want to cut Mystic Confluence or Shark Typhoon, but I may try it out in a few games.

If I don't like Bloodbraid Elf I may try out Gruul Spellbreaker as an aggressive gruul card.

Most of these changes were brought to you by a friend of mine that likes to tinker. They played the cube a number of times over the course of a few weeks while trying to get a feel for how they could build their own version. At the end of this time period they sent me a list of cards with some issues and some alternatives for those cards.

The only change I made myself is swapping Bennie Bracks for a generically better card.

Bennie Bracks, Zoologist felt kind of mediocre a lot of the time. There are ways of consistently creating tokens, but only if you specifically draft wb and find those cards. I'm also cutting retrofitter which removes a generic way of triggering him, and the best way of triggering him on on opponents turn. I'm swapping in for a generic beater Icingdeath, Frost Tyrant.

The two primary reasons for this update are Subtlety and Runic Armasaur. Both of them haven't felt particularly great. Subtlety because no one ever reads the card properly (me included). I've had too many issues with people not playing the card correctly or the card being too situational. With the lack of fetch/utility lands and with a number of creatures getting changed the armasaur feels lackluster. I played out a long game the other day and counted all the cards that had been played and only one would have proc'd the dinosaur.

Venser, Shaper Savant is a significantly better card that Subtelty that does things much more often. We lose out on the evoke value, but make up for a card that should be easier for people to play with and understand.

Heartwood Storyteller fills a very similar role as armasaur. It also plays really well into green's identity of being the creature color. Only 3 of it's 14 cards are noncreature after all.

The rest of the cards are more experiments than real balance changes.

Hypnotic Grifter looks like a great mana dump in the late game that can fuel graveyard synergies, and gives you instant speed card draw. Delver of Secrets has not impressed me. The utility of looking at the top of the library hasn't come up and the 3/2 body doesn't impact things as much as I'd like.

Robber of the Rich has been in the maybeboard for quite a while. When you are behind Robber has much better hits. In situations where you need a removal spell Robber gives you the opportunity to YOLO off the top and fixes your colors so you have a better chance of actually hitting. It also interacts with the top of the library in a way that makes your opponent (and you) think more about effects that draw or scry.

Damn is a card that you can cast without needing both W and B. That's worth enough that I want to give it a shot compared to Dire Tactics. If the utility ends up being better than exile in a lot of situations I'll make the swap permanent. If I feel like the cube needs both effects I'll probably cut Seraph of the Scales to make room.

It was brought to my attention that Realmwalker makes you pick a creature type. I am apparently illiterate. Augur of Autumn fills a similar role, but with an easier to fulfill stipulation.

I wasn't the biggest fan of Chitterspitter when I added it. Champion of Lambholt plays closer to how I want green to work. Green's job is to put creatures in play and fast. Lambholt rewards that.

Prismatic Lens is stupid powerful. Too good for the cube. Prismite is also colorless fixing, but it's easier to interact with and actively taxes you for fixing your mana. I expect it to still be strong, but hopefully not too strong for the format.

Staggering Insight is cool, and in a cube with more support for a Curious Obsession archetype it'd be good, but I don't quite think it fits this cube. Daxos of Meletis is restricted color fixing. An evasive creature that draws you cards, gains you life, and fixes colors. The card seems perfect for this cube in a slot that needed a solid replacement.

Mainboard Changelist
+1, -1

Cold-Eyed Selkie was already meh, but now islandwalk doesn't work.

I don't have a clean reason for increasing the size of the cube. Doing so is pretty easy, it doesn't make it much harder to carry it around with me. I want more slots so that tweaking cards feels easier. It'll also smooth out some of the balance of the cube.

Most of the decisions for incoming cards were based on what slots were open in that color's curve.

White

Adanto Vanguard is a pet card of mine that works really well in aggressive strategies.
Sunset Revelry is a nice comeback card which is a mechanic I think the cube needs more of.
Austere Command is a board wipe that also hits non-creatures. The cube needed more board wipes.
Giant Killer this is a neat 1-drop that can function as a removal spell late game or a way to push damage in the early game.

Blue

Preordain is just a really solid one-drop. Not much to say.
Counterspell > Remand. With the adjustment to the mana base it became impossible to hold up counterspell on t2. Remand can be cast on t2 and serves as a way to snipe a good card from the queue.
Snapcaster Mage just a solid two-drop.
Shark Typhoon is a versatile card that can always be played on curve. The instant speed draw is also a huge boon.
Subtlety. I was having a hard time finding a good four drop that I liked. I wanted something versatile. Subtlety fits the bill as a counterspell and/or creature. Subtlety's evoke ability gets weaker in this environment.

Black

Isareth the Awakener functions as a way to "cast" off-color spells that you ditched to the yard.
Spawn of Mayhem may be a bit too strong. It's very aggressive, but I'm hoping the self-ping makes it enough of a liability to keep it balanced.
Soulflayer is a fun card. There are enough haste and flying effects in the cube that it's definitely going to catch someone by surprise.
Thoughtseize probably should have been in the cube sooner. One of the issues I have had is lack of selection for removal. When a threat sticks you just have to be lucky. Hopefully thoughtseize can help keep things in check before they hit the battlefield.

Red

Goblin Guide may be too strong. It will never draw your opponent cards. But I want to buff aggro, so we'll see if I went too far.
Kari Zev, Skyship Raider. Budget Ragavan? It's a good card that has relevant keywords for Soulflayer.
Abbot of Keral Keep is another strong two drop.
Seasoned Pyromancer is a solid three drop that can fuel graveyard shenanigans.

Green

Green had a lot of changes made. I reworked the curve and made the color feel more cohesive than it did before.

Biogenic Ooze is good, but a pain to track. End-Raze Forerunners is a good chonker to ramp into that must be answered.
Beastmaster Ascension felt threatening, but never did anything. The card is either so good that it was kill on sight or so bad that it was never relevant. Realmwalker is going to be relevant even if it doesn't cast anything off the top.
Hexdrinker was terrifying, but probably not too busted; however, I wanted the slot to go to a mana dork. In comes Llanowar Elves.
Eskika's Chariot is really good, but it's not a creature itself. Master of the Wild Hunt, while not as aggressive, serves a similar purpose and is also removal.
Garruk Wildspeaker value, value, value. Helps ramp, puts bodies into play, serves as a win con if not answered.
Vivien's Arkbow this can serve as a way to clear the top of the library, can give you creatures outside of your colors, and as a decent mana sink.
Harmonize solid card to ramp into early or cast late in the game.
Chitterspitter solid token synergy. I also couldn't find a great 3 drop that I really liked.

This update will be followed by one that adds four cards to each color, bringing the total nonland card count to 100.

Mangara, the Diplomat always felt a bit medium, it didn't really contribute much to the cube. Bennie Bracks, Zoologist synergizes really well with the cube, can come down as an aggressive threat, and scales into the later turns by drawing you cards.

Mimic Vat, as much as I love the card it's just a bit too cute. This cube needs a couple more board wipes. Things can easily get gummed up and when you're behind you feel like you're drowning. Nevinyrral's Disk should help clear things out occasionally.

Treasure Map is really slow. Scry 1 is not a lot of value, and often the back side is just ramp and not card draw. Mazemind Tome should help players that are behind as well as provide more immediate value when you need it.

Relic of Progenitus it cycles and deals with graveyards. It never really feels great to play though. Unlicensed Hearse will hopefully feel a lot better to play.

Bag of Holding is a fine card and could absolutely come back, but is a bit redundant with Currency Converter. Multiple times I have played the card on t1 and never activated it throughout the game. There is a lot more of an incentive to activate Reckoner Bankbuster. The card draw feels much better than the looting.

Filigree Familiar is just a little too low on the power level scale. Skysovereign, Consul Flagship should make much more impact.

Talrand, Sky Summoner almost always was ditched during opening card selection. It's just really slow and there isn't a guarantee you'll be able to get much value out of it. Often times it's just a worse 4 mana 4/4. Fact or Fiction is definitely on the stronger side. I hope this feels fine to play and doesn't slow the game down with decisions too much.

Spectral Sailor is just too low powered. You'd hardly ever activate it more than once in a game and the damage never mattered that much. Delver of Secrets let's you peak at the next card to flip and can be a real threat.

Koma, Cosmos Serpent too strong. This was the game ender. Almost every single game ended with this card or waiting for this card to show up. It has no play and was too hard to deal with. Hydroid Krasis can't be cheated into play with show and tell for quick games, and rewards you better for ramping. Krasis hopefully won't run away with games the same way Koma did.

Beledros Witherbloom was also too strong. This was a massive game ender, often times being followed up immediately by Koma in the same turn. Without the untap ability the card would be completely fine to stay, but the ability to follow up a good threat with other plays makes this too good. Rather than a threat I decided to replace it with removal. Maelstrom Pulse can deal with large armies of goblins or Luminarch Ascension Angles. It can also deal with pesky permanents that most other cards can't.

Soulherder, I don't think I ever saw it cast. I definitely saw the card, but it never really did anything. The replacement Staggering Insight I'm not too sure about. It could be a dud, but turning an early creature into a card advantage engine, or gaining life with a blocker when you're behind could prove this card useful.

Adjustments

Tireless Tracker. Landfall isn't really all that great if tracker doesn't come down on turn three. Late game it's a pretty bad card as just a 3 mana 3/2. I made this change in paper before I decided what card should replace this. At the time I went with Runic Armasaur which has been a pretty good fit. It blocks really well and is great at pulling value out of what the opponent is doing.

Student of warfare doesn't quite feel good. Contributing resources to the board is more necessary than trying to get damage in early. Committing mana to student is almost always worse than just playing a card from your hand.

Ashiok, Nightmare Weaver is very slow. While it's possible for it to take over the game, it doesn't feel nice to play with. Hostage Taker is much more interactive and contributes better to the kind of games I want to promote.

More multicolored cards

I want to expand out the multicolored section a bit. Add some more diversity in the cards players can see and dilute some of the single colored cards that are really easy to cast.

Baleful Strix is a card that can buy you some time to gather resources or get out of a bad situation. It feels like a great card to try out.

Soulherder is the kind of card that I could see adjusting other slots in the cube to accommodate. It has some synergies with other cards: Blade Splicer, Thragtusk, Esika's Chariot. If those aren't enough I'll likely swap this card for something else or add add a few more value targets.

Falkenrath Aristocrat. There are a lot of ways to make tokens in the cube, what if we gave those a second use?

Gallia of the Endless Dance is pretty good on it's own, while also synergizing with Xenagos, the Reveler. This could be really fun or a dud, we'll find out with testing.

Dromoka's Command does a lot of the stuff missing in this cube. It counters some removal, kills enchantments, and is a pretty good combat trick.

Dire Tactics. Conditional removal with a conditional downside. This kills a number of cards in the cube that are otherwise hard to get rid of. This card may be good enough, in conjunction with other tweaks, to kick Swords out of it's slot in the cube.

The Royal Scions. Blue/Red really stumped me. I'm not sure what the cube needs that this color pair can easily provide. There are plenty of big creatures and spells matters cards, but I don't know that I want either of those. The Royal Scions are pretty good at digging for a card you want and giving an extra push to get in for damage. If this card doesn't work out I'll try out Ludevic, Necro-Alchemist.

Find // Finality seems like a pretty decent card for the cube over all. Boardwipes are appreciated since the boards can clog. It also plays really well with Pack Rat and Liliana, Death's Majesty.

Aurelia, the Warleader is just a chonker like Koma, Cosmos Serpent and Beledros Witherbloom. At four color pips she rewards the player for watching their fixing carefully. She's not as powerful as Koma, but hopefully closes out games quick enough for that not to matter. Out of all the big boros creatures I chose her for the color pips and because she dies to a bit more removal than Gisela, Blade of Goldnight and Velomachus Lorehold that were also considered.

Cold-Eyed Selkie has a landwalk ability and a relevant ability that triggers from it. I want to experiment with landwalk since it can change how the opponent picks the lands they play each turn. The selkie gets worse when the opponent doesn't grab an island, but do they want to forgo being able to cast a card in the queue or their hand?