Context

The Constrained Cube was created as an entry for the Riptide Lab 360/100 cube contest. My intention with the cube was to create a format that rewarded good drafting, led to interesting games filled with decisions and player agency, and supported a lot of different types of decks. This sounds very generic, but given the constraints of the contest I found it exceedingly difficult to put together a cube that fulfills these goals.

Cube Composition

The cube is split into "commons", "uncommons", and "rares", in a somewhat similar way to retail drafts.

There are 5 copies of each common, 2 copies of each uncommon, and 1 copy of each rare in the cube.

There are 45 commons, 30 uncommons, and 24 rares.

Also, there's 50 Prismatic Vistas in there to ensure that there is adequate fixing, bringing the total number of unique cards to 100.

Design Philosophy

Kicker
How do we make a format interesting with so few unique cards? The first mechanic I found that worked well was Kicker.

Kicker cards help this cube for two reasons:

1. They fill multiple spots in a deck's curve, giving drafters more flexibility with their picks. For example, Untamed Kavu can be a reasonable 2 drop or 5 drop. Picking them up helps avoid the chance of ending up with a deck that has too many early game threats and no late game threats and can't curve out, or vice versa.
2. During games they can lead to interesting decisions. Do I want to play Into the Roil for 2 mana to slow down my opponent or can I hold out until I can cast it for 4 mana and draw a card?

These properties are not exclusive to kicker. Cards with X in the mana cost have these same upsides:

Other Modal Cards

Cards with different modes are inherently more flexible. They give players higher agency, and can be applicable in a wide variety of situations and decks.

As an example, Charming Prince is obviously useful in blink decks, acting as a both an enabler and as a (minor) payoff. But it's also a generically useful card, one that every white deck is interested in. It can remove opposing Pacifism and Bubble Snare effects, or can Scry 2 or gain life if the situation demands it.

Tribal

While there aren't many tribal payoffs in this cube, it's really easy to support tribal themes when you have so many cards with 5 copies. For example, it doesn't take that many copies of Krenko's Command to make Pashalik Mons into a real threat.

Common Cards
Commons tend to be cards that most decks of their corresponding color would be interested in.

Uncommons
Uncommons tend to enable archetypes that would otherwise have little support. Or they add an effect that a color wants but couldn't be a common, either due to power level reasons or just because it's too niche.

Rare Cards
Rare cards tend to fall into one or both of these categories:

1. Power outliers - Draft signals
   

   

   

   

   

2. Sweet buildarounds
   

   

   

   

   

Archetypes

There are ten two-color archetypes, each indicated with a signpost uncommon.

UW: Blink

BW: Aristocrats

RW: Aggro/Go-wide

GW: Tokens/Go-wide

UB: Ninjas

UR: Card Draw/Spells Matter

UG: Ramp/Lands Matter

BR: Aristocrats/Aggro

BG: Graveyard

GR: Stompy

Other Themes

You're not locked into drafting a two-color deck by any stretch. Here's some other themes:

Rx Goblins

Destroy your opponents by throwing goblins at them. Any red deck can support this if you get the right cards.

Esper ETB

Abuse powerful ETB creatures with ninjas and blink effects. And this isn't limited to Esper, you could also branch into green for strong ETB effects:

Madness

Get value out of discarding cards.

Mardu Aristocrats

Make the ultimate aristocrats deck by going three color.