Summer Collectifun is the summer event in Shakes & Fidget. For a specific period of time, you get several tasks from Goblin Gleeman in the quarter.
You get one point for every task. The goal is to collect a minimum of six points at the end of the event to gain a legendary gem.
On the way to the goal there are two intermediate goals: you'll get gold for two and four points (amount scales with your level) and the option to buy an additional beer in the taproom.
In total, more than the 6 points needed for the final reward can be collected, so you do not have to complete all tasks.