Guilder
02-15-2015

In theory, this relic theme for Ong Khan's armor should be available if you have the right Adept of Age chrono title. It's 15th Century-based; some Japanese sites listed it as belonging to Period 5, but I can't see the theme with the Adept 15.5 title equipped, so it's possibly 15.4 instead. If anybody finds out for sure, please let the rest of us treasure hunting completionists know.

Destry1
03-04-2015

According to the Japanese wiki this theme is related to a historical event of the 15th century, period 5. In this period there are 2 possible events (and maybe a third), one is Arrival in the new world, and the other is Arrival at the cape of good hope. This second one seems to be the trigger to unlocking the TH. So chrono titles cannot be used...

Guilder
04-23-2021

With the historical event's arrival on Maris server, this theme is now permanently unlocked.