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Platform: Windows
ISP: NA
Type of Internet Connection: Cable
Internet Connection Speed: 252.01
Date & Time: NA
Frequency: NA
Character Name: Elli
Race: Hume M
World: Cerberus
Main Job: Blu
Support Job: War
Area and Coordinates: Nashmau
Party or Solo: Solo
NPC Name: Paparoon
Monster Name: NA
Steps:
1. Note: You do not need to defeat all of the aforementioned monsters again when making another Mythic Weapon.

Simply trade Abquhbah your weapon and speak with Naja again.
You will have to abandon your old weapon even though its been completed.
Once you abandon your old weapon, you will have to trade your new weapon a second time to start the quest.
If you have any issues receiving the cutscene from Naja of Paparoon requesting you visit Nashmau, after speaking to her multiple times. Then zone and try again in order to receive it. this is what i did as i received the next CS to talk to Paparoon to get my 5 books.
2.Talk to Paparoon on the first floor in (G-7) Nashmau and select every option. Upon asking about Assault Memoires, you will receive 5 items. He will give you the five assault logs for recording the re-completion of each Assault.
If you do not have 5 open spaces in your Gobbiebag, the cutscene will be cancelled.
Obtain the required items:
Salvage: (and Nyzul Isle Uncharted Area Survey):
Alexandrite 30,000 Alexandrite (or 1 Cat's Eye from Mog Bonanza)
Note that trading a Cat's Eye will complete the Alexandrite requirement but any previously traded Alexandrite will be lost. If you are significantly far with your Alexandrite progress, consider finishing it with Alexandrite and using a Cat's Eye on your next Mythic Weapon instead.
Nyzul Isle:
Purchase a Wyrmseeker Areuhat Copy of Wyrmseeker Areuhat from Zasshal with 150,000 Nyzul Tokens.
Einherjar:
Purchase a Balrahn's Eyepatch Balrahn's Eyepatch from Kilusha with 100,000 Ampoules of Therion Ichor.
Assault:
Show proof of once again completing all 50 assaults by trading the corresponding one of the following items to the Rune of Release at the end of each assault:
Ilrusi Ledger Ilrusi Travel Ledger
Periqia Diary Periqia Adventure Diary
Lebros Chronicleh Lebros Exploration Chronicle
Mamool Ja Journal Mamool Ja Battle Journal
Leujaoam Log Leujaoam Observation Log
Each completion log item will be marked with assault completions in the item's help text (far right = PSC rank, far left = FL rank)
Note that if you decide to change weapons, all progress on this quest will be reset (any traded Alexandrite or items will be lost and Assault logs will need to be dropped so they can be received again before the quest can be restarted).
Once all the items have been given to Paparoon, speak to him again to receive Key ItemPaparoon's sealed invitation.
3.i finished all objectives as seen in my screen shots but not receiving the CS to move on to the next quest line Forging a New Myth. i have tried multiple times trading a weapon to Abquhbah to make sure it is still on Dancing Dagger and it is, and say never every time. plus i went to palace to check if I can go in but no dice. I'm at a lose of things to try. I uploaded screen shots to try and help.
4.https://imgur.com/8k5yCgFhttps://imgur.com/RySHy1uhttps://imgur.com/jG6b1mUhttps://imgur.com/GBuQEwahttps://imgur.com/a6PM7fchttps://imgur.com/H2GY9LAhttps://imgur.com/O3FZz9Phttps://imgur.com/t19PHNK