How can I get Royal Bounacean Advisor Outfit?

Question

What is the process of getting full Royal Bounacean Advisor Outfit? I understand that I need to defeat the Megasylvan Yselda, but what else I need to do to get full outfit?

Answer 1

Base Outfit
Finish the Adventures of Galthen Quest by defeating Megasylvan Yselda and report to Kesar the Younger.

First Addon
Defeat Megasylvan Yselda while keeping her Saplings alive (see Adventures of Galthen Quest) and talk to Kesar the Younger. Talk to John (Bounac) in his house, at night, about Yselda to receive the addon.

Second Addon
The second addon is not obtainable yet, as confirmed by CipSoft during the Test Server in which the outfit was implemented. 

Source: https://tibia.fandom.com/wiki/Royal_Bounacean_Advisor_Outfits_Quest