Crownroaches

Generally a power card is ran in Markets in case you get stuck on power. This deck runs pretty light on power even with the ramp from both Initiates and Merchants. The reasoning behind a Banner is that if you play the Merchant on 3 you get undepleted power which you could use to play Initiate or Permafrost if needed.

As for the rest of the Market first I should mention about the reasoning behind running two different Merchants. Since Crown is a 2f card it can be bought from the Market by Merchants of both factions. So, essentially you are running 11 copies of Crown which would give you ~80% chance of hitting either a Merchant or Crown on turn 3. That doesn't account for drawing cards through Scribe, Second Sight, nor Wisdom. Disjunction is flexible in that it can be used for either getting back a Crown that your opp discarded, used Disjunction on, taking off Austerity, or hitting opp's Masks, Obelisk etc.

As for Twinbrood and Dragon I've gotten in the habit of building Markets similarly with other decks that run 2 different Merchants. It gives you some added flexibility in being able to pull out a bomb no matter which Merchant you happen to have. Both are typical bombs ran in Crownroach decks, and it's nice to be able to pull them out if you already have a Crown out or an Alhed on board.

The ladder meta is pretty unfriendly to Crownroach decks I've found at the moment. This particular list is a bit more all-in on the Combo aspect of Crown+Roaches. If it seems like you don't have enough time to setup with your combo you might want to try a different approach to Crownroaches depending on the meta, either making it more midrangey or splashing another color for removal. Shadow is a common color for the removal approach because there are several easily splashed spells like Annihilate, Vara's Choice, Banish etc. all of which have different benefits and are cheap.

This list is defintely a wip, I'm barely getting around to playing with Crownroach decks with the release of FoA even though they're typical one of my three most played decks.