Map of Thayan Enclaves

 based on this post, here's a map of enclaves, which is helpful for this pub.

Red Wizards of Thay

 Of all the cannon and homebrew factions in D&D, the only one specifically not allowed in Adventurers League is the Red Wizards. Despite that, I think it would be fun to play one that's going out into Faerûn to collect magic items of power to send back to the homeland and for overall espionage work. For adventures in and around Waterdeep, the Red Wizards are in Skullport (they're specifically banned from having a formal presence in Waterdeep itself) with both emissaries and intelligence gatherers. Here's the Red Wizards of Thay built out as a player faction if you're interested.

Three Factions of Waterdeep: Bregan D'aerthe, Gray Hands, and Xanathar Guild

Bregan D'aerthe, Gray Hands, Xanathar Guild...these three factions play a significant role in Waterdeep - Dragonheist. Three Factions of Waterdeep expands and integrates those faction rules and benefits into one cohesive resource, further detailing various ranks and their associated perks. The writer took a similar approach to the publication Guide to the Five Factions. It includes:

• By-faction perks for ranks 1-5.
• Summary of renown rules and short background of each faction.
• A magic item for each faction representing the various faction insignias with descriptions of the faction perks, with D&D Beyond links that provide the player quick access to the perks, promoting character involvement.
• Factions membership cards which can be used as handouts with QR code on the back linking to the D&D Beyond magic item.
• 2 Gray Hands subfactions with perks:
  • Force Grey.
  • Deep Delvers.
• Equipment including a fully detailed drow gunslinger's pistol (with five types of ammunition), spelunking pack, faction loot satchel, and spidersilk rope.
• PNG files of wax seals for faction letters and missives, for all three factions and the two subfactions.
• Downtime faction jobs unique for each factions.

The Five Main Factions of Faerun

 Here's my own attempt at a guide to the five main factions of Faerûn, whether you're in Waterdeep or anywhere else in Toril. Guide to the Five Factions attempts to consolidate and build off of the official fifth-edition faction rules, Adventure League season 10 renown rules, and some legacy and other third party publications to make it easier to incorporate factions into your adventure. It includes:

• By-faction perks for ranks 1-5.
  
• Summary of renown rules and short background of each faction.
  
• A magic item for each faction representing the various faction insignias with descriptions of the faction perks, with D&D Beyond links that provide the player quick access to the perks, promoting character involvement.
• Factions cards as handouts with QR code on the back linking to the D&D Beyond magic item.
• Letter templates to assign missions as player handouts, which also includes a paper bird (magic item from Waterdeep: Dragon Heist) .doc that includes printing and folding instructions to fold the message up into an origami owl - so a DM can physically hand a faction missive to a player at a gaming table.
• 2 subfactions:
• Zhentarim Doom Raiders as discussed in Waterdeep - Dragonheist.
  
• Emerald Enclave Instars including two monsters with D&D Beyond links: the moth and the butterfly.

Here's a look at the faction cards and the wax seals.

A Forger's Guide to Waterdeep

 After spending a significant amount of time buried in GIMP, I've finished The Forger's Guide to Waterdeep. It originally started as me wanting a master forger to put into my campaign, and it expanded significantly from there. It now includes a small pile of assets for anyone looking to build a forgery scenario into their adventures, wanting more realistic wax seals for their missives, or wanting a character to become a master forger. The included seals cover all the major organizations found in Waterdeep - Dragonheist, Waterdeep - Dungeon of the Mad Mage, and Curse of Strahd (with numerous other organizations covered in legacy Waterdeep publications). This publication includes:

• A summary of the rules of forgery and forging equipment
• 174 unique digital wax seals listed below with PNG files (plus a couple other failed forgeries and a variant for RP purposes), which can be printed out on notes, titles, deeds, orders, whatever
• A Master Forger NPC
• A hook to get a character down the path of becoming a Master Forger

Waterdeep (and Skullport):

• 23 Factions: Arcane Brotherhood, Bregan D'aerthe, Emerald Enclave, Gray Hands (and Force Grey subfaction), Harpers, Iron Ring, Keeprs, Knights of the Shield, Kraken Society, Lords' Alliance, Order of the Gauntlet, Red Sashes, Red Wizards of Thay, Sha'Sal Khou, Shadow Thieves, Tel Teukiira, Unseen, Xanathar Guild, Zhentarim
• 15 Temples: Gond, Helm, Ilmater, Lathander, Mystra, Oghma, Selune, Sune, Tempus, Tymora, Tyr, and Umbrelee. As well as the Holyhands House, Temple of the Seldarine, and the Shrines of Nature.
• 78 Noble Houses: Everyone from Adarbrent to Zun
• 44 Trade Guilds: Everything from the Apothecaries & Physicians Guild to the Wheelwrights' Guild
• 2 Cities: Skullport, Waterdeep
  
• 5 Governing Bodies: Lords of Waterdeep, Waterdeep City Guard, Waterdeep City Watch, Waterdeep Griffon Cavalry, Waterdeep Navy

Barovia (including as a bonus):

• 2 Factions: Keepers of the Feather, Order of the Silver Dragon
• 5 Houses: Durst, Martikov, Strahd, Vallakovich, Wachter