Thieves Guild members will get increased drops from heists, and Dark Brotherhood members will get increased drops from sacraments. In last year's event flawed Heists gave the reward for perfect Heists, while perfect Heists gave double the crates. While ZOS haven't specified in their official posts yet, I'm expecting this year's event to work the same way.
For those not of a stealthy persuasion, you'll get double drops from World Bosses & delve bosses in Hew's Bane and the Gold Coast, also from Maw of Lorkhaj. There's also double harvesting resources from regular crafting nodes in these zones (not nodes from Survey Reports).
There's also the chance to catch up on many Motifs: Outlaw, Thieves Guild, Assassins' League, Dro m'Athra, Dark Brotherhood, Minotaur, and Order of the Hour! You can also get Abah's Watch Motifs from Thieves Guild tip board quests - these aren't double drops. Check the wiki to
find out where each motif drops.
There's plenty for everyone, but especially for newbies. Double drops in Hew's Bane and Gold Coast nodes will get you a big pile of raw materials and flowers quickly, which you can sell in Guild Traders to make gold. Double drops from bosses will grant weapons, armour & motifs.
And if you don't already own the Thieves Guild or Dark Brotherhood DLC, they are reduced in price during the event to 500 crowns each. If you want the Collector's Bundles with pets and mounts, they're 1600 crowns each. All until 2pm GMT (10am EDT) on 12th March.
