To unlock the Medieval Armor you have to do two things, first, solve the 18 Nostradamus Enigmas and second, complete the 3 Rooms, that are also have Riddles and climbing section, in the Cafe Theatre. After these two things you can get the Medieval Armor.
The Start Point of the 18 Nostradamus Enigmas see you on your Map, when you sync the Viewpoint in this district. The Icon for the Enigmas is a paper roll. (i want to add a Picture but TA supersize this every Time, no Idea why... )
The process of the puzzle is always the same, you go to a Icon, start the Enigmamission and then you have to find 3-4 symbols with your Eaglevision and interact with them. The Symbols can be everywhere, on the floor, on a wall, a tower etc
My Videoguide below shows only as Video the Symbols and the Start Point as Picture with a red dot marked Enigma. In the Spoiler below the Video is the Timeline and all 18 Names of the Nostradamus Enigmas.
*** Spoiler - click to reveal ***00:06 - Nostradamus Enigma Aquarius
02:12 - Nostradamus Enigma Aries
03:42 - Nostradamus Enigma Cancer
06:15 - Nostradamus Enigma Capricorn
07:40 - Nostradamus Enigma Gemini
09:24 - Nostradamus Enigma Jupiter
11:00 - Nostradamus Enigma Leo
12:29 - Nostradamus Enigma Libra
14:10 - Nostradamus Enigma Mars
15:44 - Nostradamus Enigma Mercurius
17:25 - Nostradamus Enigma Pisces
20:13 - Nostradamus Enigma Sagittarius
21:45 - Nostradamus Enigma Saturnus
23:39 - Nostradamus Enigma Scorpio
25:07 - Nostradamus Enigma Taurus
26:55 - Nostradamus Enigma Terra
28:40 - Nostradamus Enigma Venus
30:09 - Nostradamus Enigma Virgo
After you solve all 18 Nostradamus Enigmas, you can go to the Armor Room from the Cafe Theatre. Here are 3 closed Rooms, to open the first Room you need 4 complete Nostradamus Enigmas, for the second Room 10 Nostradamus Enigmas and for the last all 18. To open a Room, interact with the circle "thing" in front of the Armor.
In the
first Room (right Side) you find 4 Pillars. You have to interact the Pillars so often to solve the first Room:
South - 2 times
West - once
North - 3 times
East - 2 times
Should you have totally twisted you for some reason, then look to the Wall. There you see the symbols that belong together. So looking at the ground which Symbol is and then finds the correct other writing on the wall and rotate the pillar so out.
Then you have a climbing passage to reach the lever for the first barrier on your Way to the Medieval Armor. Watch the Video for the climbing passage, its a little bit "tricky"
In the
second Room (left Side) there is a planetary model and before 3 switches with which you can interact. Interact with the left 3 times, with the middle once and with the right again 3 times.
Should you have totally twisted you for some reason, look to the planetary model and rotate so often that all the planets lie on a line from left to right and match their color balls that are embedded in the floor.
The
third Room is really easy. It is only a climbing Passage with steam traps. Take your Time and climb to the last lever to unlock the last barrier.
If you complete all 3 Rooms, the entrance to the Medieval Armor is free. Get your Medieval Armor and the Achievement unlocks. to equip the Armor, go in the Character Customization menu and equip the "Thomas de Carneillon's Master Assassin Outfit"
Here is a Video with all 3 Rooms: