A 540-card cube built from all Ravnica sets.

Notes on card selection:

• This cube tries to build more on synergy between cards than on the raw power level of individual cards. There are certainly strong individual cards in the cube but most of these also support one or more of the guild archetypes.
• I use cards from other sets/products that take place on Ravnica (a list of these types of cards can be found here: https://www.mtg-multiverse.com/#/ravnica/ ) as well as from Ravnica Duel Decks.
• Additional fixing is added to the cube through multiple copies of guild-gates and shocklands. There are 1 shockland and 4 guild-gates/guild except for Boros and Rakdos that have 2 shocklands and 3 guild-gates as they usually need untapped lands more. The guild-gates are there to support certain strategies built around gates.
• I limited the number of planeswalkers in the cube to max one pr. mono-color and/or color pair because the number of interesting planeswalkers in a Ravnica setting somewhat limited. I mostly include planeswalkers that support one or more guild archetypes well.
• A few cards are allowed to show up multiple times. As for now a card can show up max 2 times (except for guild-gates) to push specific mechanics that I feel would have too little support otherwise. Only 4 cards show up 2 times so it's just a minor balancing.
• A few cards could be a bit too strong for the cube. Cards like Nissa, Who Shakes the World (currently not in the cube), Thief of Sanity (currently in the cube) and a few others are to be decided...

Notes on card distribution

• Since this is a Ravnica-cube it is only natural that there are a lot of multicolored cards. However I also think that it is important that the multicolored cards don't overwhelm the cube as it can limit the number of avaiable options in each pack too much and make the cube feel a bit too forced/restrictive. For this reason I have chosen that each guild should have about 16 multicolored cards of which at least 3-4 use hybrid mana.
• There are 25 artifacts and 60 lands. The lands are shocklands and mostly guildgates (as guildgates synergizes with certain cards). This leaves around 50-60 cards for each mono-color. In each of the 5 colors there are about the same number of cards to support each guild archetype although with respect to certain cube principles such as supporting aggro with more creatures than control to make it viable etc.
• The number of cards in each color might vary a little bit but it should even out if hybrid-mana cards is taken into consideration.

The mechanics and archetypes:
The cube aims to mix the guild mechanics from the sets although it focuses mainly on 1-2 mechanics per guild. Below the mechanics are listed for each guild as well as their main available strategies.

Azorius:
Mechanics: Forecast (Rav), Detain (RtR), Addendum (GoR).
Main strategies: Control or Detain-Aggro.
Azorius' gameplan is usually to be the control archetype. All the 3 guild mechanics support this well so the guild has a lot of options. The detain mechanic can also be used in a more aggressive way to lock down the opponents blockers.

Orzhov:
Mechanics: Haunt (Rav), Extort (RtR), Afterlife (GoR).
Main strategies: Life-Gain and/or Token/Sacrifice.
Orzhov's gameplan is usually to be a grindy midrange/control deck. Extort makes it possible to win through small incremental damage. Afterlife is also great with the sacrifice archetype in black, red or green. Orzhov can also follow a life-gain strategy through cards like Karlov of the Ghost Council, Dawn of Hope etc. I find Haunt to be a bit clunky so it is not found on many cards in this cube.

Boros:
Mechanics: Radiance (Rav), Battalion (RtR), Mentor (GoR).
Main strategies: Aggro with go-wide and/or +1/+1 counter themes.
Boros is on of the two aggro-archetypes. The gameplan is usually to overwhelm the opponent with creatures and utilize the Battalion and Mentor mechanics to win fast. Burn spells also support this archetype.

Selesnya:
Mechanics: Convoke (Rav + GoR), Populate (RtR).
Main strategies: Populate/Tokens and/or Life-Gain and/or +1/+1 Counters.
Selesnya is a go-wide archetype usually through tokens with the Populate mechanic. I found that Selesnya in general lacks ways to make tokens that are not 1/1's and thus lacks ways to gain enough value from populate to make it worth it. I have therefore included multiple copies of certain cards that make 3/3 tokens early on: Call of the Conclave and Centaur's Herald. Hopefully this is enough, but I am open to include more token generators if it is insufficient.

Dimir:
Mechanics: Transmute (Rav), Cipher (RtR), Surveil (GoR).
Main strategies: Surveil-Control and/or Mill.
Dimir's gameplan is usually to be a control deck but other options are available as well. Surveil supports graveyard interaction and mill is also a very viable option. Surveil is very well supported and Transmute are used on a few cards - but I found the Cipher cards in general to be overpriced and not good enough for the cube.

Izzet:
Mechanics: Replicate (Rav). Overload (RtR), Jump-start (GoR).
Main strategies: Spells-Matter synergy.
Izzet usually follows a "spells matter" gameplan. All the 3 guild mechanics support this well and there are plenty of creatures that provides value through instant and sorceries.

Simic:
Mechanics: Graft (Rav), Evolve (RtR), Adapt (GoR).
Main strategies: +1/+1 Counters and/or Control.
Simic is the +1/+1 counter deck. All 3 guild mechanics support this strategy in various ways and there are a lot of cards that gains additional value from counters.

Rakdos:
Mechanics: Hellbent (Rav), Unleash (RtR), Spectacle (GoR).
Main strategies: Aggro and/or Sacrifice.
Rakdos in general has two possible gameplans: aggro or sacrifice. Aggro is pretty straight forward: Both Unleash and Spectacle supports and rewards this strategy. However there are also plenty of sacrifice support in both sacrifice enablers, value creatures and anchor cards. I find Hellbent to be a somewhat boring mechanic so it is not used too much in this cube.

Golgari:
Mechanics: Dredge (Rav), Scavenge (RtR), Undergrowth (GoR).
Main strategies: Graveyard-synergy and/or Ramp.
Golgari usually wants to build on graveyard synergy that is supported by all 3 guild mechanics. It has access to ramp a few sacrifice options as well.

Gruul:
Mechanics: Bloodthirst (Rav), Bloodrush (RtR), Riot (GoR).
Main strategies: Ramp and/or +1/+1 Counters.
Gruul is the ramp arhcetype that combines aggro with ramping into big creatures fast. It synergizes very well with the +1/+1 counter archetype.

Other: Additionally there are two War of the Spark mechanics: Proliferate and Amass. Proliferate is featured on a few cards to support the +1/+1 counter strategies. Amass is also used on a few cards as I find it supports the sacrifice strategy pretty well. There are also a few cards that value guild-gates such as Guild Summit and Gate Colossus as well as cards that can utilize 5-colors as a pay-off for collecting guild-gates.

Feel free to comment/suggest changes to the cube :)