Find Magister Tassi in Lion's Arch. She is located to the North of the Gate hub. Speak with her and you will receive a letter containing instructions, Matter Meter and a Trick or Treat bag. Open up the bag to get your Candy Corn which will be used by the Matter Meter.

Use the Matter Meter near Magister Tassi, then use the skill Etheric Field Scan. Spirit Serene will then appear. Talk with Serene.

Mad Memoires Site 1
Dig deep in the Muck, where all the garbage of Lion's Arch flows.
Mad Memoires Site 2
Search the dead streets and forgotten thoroughfares of another Lion's Arch.
Mad Memoires Site 3
Say more now and look more where Kryta's descendants are buried.

For steps 4 and 5 please use the guide at the folling location Mad King Scavenger Hunt Guide

If you are having diffculties with Clock Tower Jumping Puzzle, come check out the following video: Mad King's Clock Tower

Some of the jokes I have come across from the Mad King: Mad King's Jokes