Based on new update for Yong Shield !
Mostly the quest same with Yong Weapon to earn the heart for each job (Refer to guide #332 - Yong Weapon Quest)

To proceed with this quest, you have to be minimum rein 10 (Lv 109) and already finished 'Found the Path to Mount Haku' quest (Because you will need to get the item from rift boss).

If you have already done all of it, the 1st step you need to do is defeat rift bosses until you get the hearts.

Warrior will need Heart of Ma,
Mage will need Heart of Rang,
Poet will need Heart of Kyum, and
Rogue will need Heart of Chun.

Bring the heart to Trowulan Palace, and go to the library. In the library go to the secret room (009,004).

With the heart in your inventory find the book of 'Secret of Yong SHIELD' (Do not click the Yong Weapon, instead of you want to made it that!)
It will appear randomly (Not always in the same spot!) so be patient. Press "o" while facing the bookshelves to find the book!

Once you find the book, click to read, and it will ask you to bring all these items.

4 pcs of Wooden Shield (Creation - Guide #28)
4 pcs of Iron Shield (Creation - Guide #28)
4 pcs of Round Shield (You can only get from GIFTBOX !!!)

4 pcs of Bjorn/Dowhar Shield (Warrior & Rogue: Bjorn, Mage & Poet: Dowhar - Item exchanged by 250 point)

4 pcs of Bjorn Hide Shield/Dowhar Mystic Shield (Item exchanged by 500 point)

2 pcs of Tsunami Guard
4 pcs of Water Shield
4 pcs of Thunder Shield

After all submission, it will show you the recipe to create Yong Shield.

Recipe for Yong Ma (Warrior):
1 Barbed Choker,
1 Holy Barrier,
1 Heart of Ma

Recipe for Yong Chun (Rogue):
1 Black Pendant,
1 Holy Barrier,
1 Heart of Chun

Recipe for Yong Rang (Mage):
1 Magic Rune,
1 Holy Barrier,
1 Heart of Rang

Recipe for Yong Kyum (Poet):
1 Frozen Heart,
1 Holy Barrier,
1 Heart of Kyum

*** Need further confirmation because no one try creating Rogue's shield yet! ***

During creation process, 1 Heart (basic success rate) gives you 30% success rate which mean adding more heart gives you bigger chance of success (adding 2 heart means your success rate is 60% and so on).

If the process failed, everything gone! WKWKWK !!!

Credit to Culdesac & Dominic
Who helped to crack the quest !

-godsgas-