Bandit Crests are a new "currency" added with the release of Living Story Season 2, Part 5: Echoes of the Past. They can be used to obtain skins, among other things. For the skins, it takes 1,000 crests for each piece.
What's the fastest way of obtaining a lot of Bandit Crests?
Best Answer
Farming the events in The Silverwastes is the fastest way I've found. As the events chain together back to back, you can get lots of bonus chests for completing these events and also some crests for failing some of the events.
So go find a fort and hang out there, helping dolyaks, defending the fort and also rebuilding walls. You can roam away from the fort to take on the marked veteran enemies which count as an event too.
As for the skins, you're actually better off earning them through bosses. If you complete the personal story you'll get one skin. After that the skin will drop again if you complete the map event of killing all 5 champion bosses within 4 minutes of each other.
I would recommend spending your crests on Bandit Lockpicks as when a player finds a chest using a shovel it is visible to all players. Each chest contains a champion loot bag, which will probably net you more money.