Assistant Clever King is a Quest NPC.During specific times/when announced, players level 20 and above can play the daily event Word-bingo with her.
When the announcement is made that the event has started, register with the Assistant Clever King in Eversun City. She is located near the bank.
Once you are registered you are given a ticket with a countdown timer on it. Your task is to locate the words "Dream", "of", "Mirror", and "Online".
To locate the words, hunt for the various chests located throughout the city. Click on the chest and after a small loading timer finishes the chest will open. You will either get one of the words or a small amount of consumables such as frogs, arrows, bolts, etc. In rare cases you can get an Onyx.
Once you have all 4 words go back to the Clever King and turn in your ticket. If you are one of the top 5 with the fastest time your name will appear on the announcement banner.
If you are not top 5 you will not get the announcement.
July 2018 updateEdit
You can now get onyxies for the new set armors with a normal drop rate (not rare ones as previously):