Gems of War

This is tied to the "Paths" event. It is unknown at this time if/when they are going to repeat it. Your path name may vary from mine because they are tiered based upon player level. Since I'm over level 1000 (1417 right now) , mine is referred to as the Exalted Path. From the main map, there is a circular emblem beneath your three ribbons in the top middle. Once you access the Path window, you will see a Daily Progress section. It contains three tasks to be completed within the day.

As an example today's are (at least for me) 1. Win 5 PvP battles. 2. Earn 10k gold. 3. Cast 50 spells. My three from yesterday were 1. Complete a dungeon run. 2. Collect 200 souls. 3. Match 200 blue gems. So far none are that daunting for an experienced player. They may be depending on your level.

Upon completion of three, the achievement pops. I got mine before even reopening the Path window again. Upon completing the tasks, you can also claim a prize for completing the challenge. Yesterday and today it offered a 15 minute XP boost.