At first I thought you just have to collect 4 map pieces.I was wrong . I saw other progress faster while I was moving like a turtle.Then my one of friend told me to collect map pieces without dying.Then I finished it with fun and no time.
So here are some tips for you -
a) Map pieces spawn in 4 different parts of the playable maps.Learn where they spawn.
b)No mercy, kill any enemy in sight.Or they will slow your progress.You could team up with them if they moonwalk.
c) Each map piece have its own unique color .So when they spawn they highlight the area with their unique light (orange, green, blue, violet). So be alert.
d)Collect every pieces without dying.It gives you progress and gold bonus.If you die no worry,again get 4 pieces without dying.
e) Use Bunny pants to attract them.Dont camp a map spawn like a noob. :)
This will help you progress faster and making some handful of gold.So the event will be fun for all.Aye boys get crackling!