This will be a card and mechanics page for my first custom set Cazia. I am currently writing a series in blog form about how I developed Cazia, focusing on the connections between theme, flavour, and mechanics. I will post relevant links to blog posts and other threads in different parts of the forum as they are written. Please treat this page more as a reference and a place to discuss the general direction of the set than specific cards or mechanics, so that it doesn't get cluttered with unnecessary comments.
I just want to point out how differently we go about set design. My top-down sets are very focused on using characters and story to support flavor, and I put much more weight on mechanics. Your sets start from the ground up, building a visceral feel that transports you to another world. I think we compliment each other and I hope to work more with you on making sets.
About Cazia, you have two controversial mechanics, Dunes and Ruin. I strongly support the former and strongly oppose the latter. I think using a sixth basic land type (but not a new color) is the perfect design space to explore in an Ancient Egyptian themed set. I even did the exact same thing before I put my Egyptian set on hold.
However, Ruin is not something I think you should explore. Variance is something I know is necessary as a designer, but it's something I HATE as a player. Mana screw or flood is by far the biggest cause of unpleasant experiences in Magic. I even spent hundreds of dollars on WoW TCG a few years ago because I didn't want to have 1/5 of my games be decided by mana screw. As a player, if I saw Wizards preview a block that featured a mechanic that promoted players mana screwing each other, I would have to relegate my Magic to Commander or Cube for the next year. If you want to work in this area of design, it should be at high rarities and it should serve a specific function for constructed. Any more than that and you will lose a lot of players.
Is this a set with factions? (Scars, RTR, and Khans have factions while Zendikar, Innistrad, and Theros do not) If so, I'd recommend spending time on them because that's something that should be explored before you play with mechanics.
Mulldrifter7 thank you for the comments. I call the way I design "thematic design", a concept similar to Doombringer and Stairc's idea of "cinematic design". One of these days I will write a post on the subject, probably as I near the end of my series on Cazia, Deadworld and move onto Cazia Restored.
Ruin was the first mechanic of Cazia, but it was by no means the last. So far I've revealed only a quarter of the major mechanics I've looked at including in the set, and I think everyone's opinion on Ruin will change by the end of Cazia block.
All good sets have factions, a topic I will explore in a future post when I go through the colour archetypes of Cazia. At the moment the vast majority of material I've introduced are concepts and themes, nothing is concrete. As a more specific answer to your question, no I don't have watermark factions like in RTR, Khans, or Scars (Alara should be on that list too, dammit Wziards).
I've added another blog post, this one on the last remnants of the kingdom of Keb.