The Path of Dawn - The Elder Scrolls IV: Oblivion
If you speak to Jauffre once at Cloud Ruler Temple, he asks if you'd like to join the Blades, the group of warriors tasked with defending the Emperor at all costs. Joining the Blades is not necessary in order to progress in the main storyline. If you do join, however, Jauffre will give you an Akaviri Katana. Furthermore, Blades armour can be found in the Cloud Ruler Temple West Wing.
When you've made your choice, select the 'Amulet of Kings' dialogue option while speaking to Jauffre. He wants you to contact Baurus, who can be found in Luther Broad's Boarding House in Imperial City. Jauffre believes that Baurus may have information regarding the assassin group that swiped the Amulet of Kings from Weynon Priory. Luther Broad's Boarding House is located in the Imperial City's Elven Gardens district. Unless you're up for walking, just fast travel there from the exterior of Cloud Ruler Temple.
After fast travelling to the Elven Gardens District, head straight until you reach a junction, at which point turn left to spot Luther Broad's Boarding House. Head inside and locate Baurus, who should be sitting on one of the barstools in front of the counter. Sit down and speak to Baurus. He explains that in a moment, he is going to stand up and leave the boarding house, and the man seated in the corner is going to get up as well and follow. Baurus wants you to follow this man. Just select 'I'm ready when you are' from the dialogue options, as Baurus is unwilling to discuss anything else at this time.
Retrieve the Mythic Dawn Commentaries 1 volume from Astav Wirich's corpse.
Wait until the man stands up and begins following Baurus before getting up yourself. Follow the man into the basement and wait until he attacks Baurus, and then take him out. When the man is dead, search his corpse and retrieve the Mythic Dawn Commentaries 1. When you have the book, speak to Baurus once more. Ask him what should be done next, and he'll tell you to see Tar-Meena at the Arcane University. Tar-Meena is the Imperial City's resident Daedric cult expert, so she may be able to interpret the Mythic Dawn volume you've acquired.
Make your way to Arcane University, which is located in the southeast corner of Imperial City. Once you're there, walk up to the door and step inside. Tar-Meena is a female Argonian who can likely be found in the Arch-Mage's Lobby. Speak to her and select 'Mythic Dawn' from the dialogue options to learn a bit about the cult. Afterwards, tell her about the book in your possession. Tar-Meena explains that there are four Mythic Dawn Commentaries. She has the second volume in her possession, and is willing to part with it. The First Edition bookstore in the Imperial City's Market District apparently carries the third.
Speak to Tar-Meena in the Arch-Mage's Lobby at Arcane University to acquire the second volume.
Leave Arcane University once you have the second volume and fast travel to the Market District. Once you're there, just head straight, past the junction, and look for the bookstore along the left side of the road. Head inside and speak to Phintias, who is the proprietor of the First Edition. Select the 'Mysterium Xarxes' dialogue option; he tells that while he has a copy of the third volume on hand, it has already been paid for by another customer. Ask him about Gwinas, the man who has purchased the book, and Phintias will explain that he is late for the pickup, but should be arriving shortly.
Stand off to the side and wait for Gwinas to arrive. When he arrives, allow him to walk up to the counter and obtain the book from Phintias. Once he has the book, speak to him and ask about it. Gwinas explains that he was unaware that the Mythic Dawn group assassinated the Emperor and his sons. Upon realizing this, he wants nothing to do with the Mythic Dawn cult and is happy to part with the book. He'll then tell you of the fourth volume, which can be obtained by speaking directly to a member of the Mythic Dawn cult. Gwinas explains that he had an appointment set up to meet with a man known as the Sponsor to obtain the fourth book; he'll then give you a note with directions to the meeting place.
The note instructs the reader to enter the Sunken Sewers beneath the Imperial City and sit at the table there. But first, make your way to the Elven Gardens District and speak to Baurus to tell him what you've learned.
Intercept Gwinas after he picks up the third volume from the First Edition bookstore and inform him of the royal assassination connected to the Mythic Dawn group to receive the book.
Enter Luther Broad's Boarding House and Baurus will automatically initiate a conversation with you. He insists on coming along to the meeting, as he claims to know his way around the Sunken Sewers. Follow Baurus out of the boarding house and he will eventually lead you to a grate to the Elven Garden Sewers.
It is quite dark in the sewers, so bringing along a Torch or casting the Nighteye spell would be a good idea. To get to the meeting place, follow Baurus and help him fight enemies encountered along the way. Don't run ahead, as Baurus will not follow you and just freeze in place until you fall back behind him.
When you reach the stop, Baurus will stop and initiate a conversation with you. He wants to sit for the meeting while you keep watch. At this point, Baurus is no longer immune to death; if his health falls to zero, he's dead. If you keep Baurus alive and speak to him after the quest, he can raise your Blade and Heavy Armor skills by one point. So, if you want to keep him alive, tell him that you will meet the Sponsor while he keeps watch.
Afterward, head through the door and enter the Sunken Sewers. Approach the table and sit down in the chair. The Sponsor will enter the room and begin speaking to you. A little ways into his briefing, he discovers that you did not come to the meeting alone as instructed.
Meet with the Sponsor in the Sunken Sewers. Kill him and loot his corpse to find the fourth volume.
You have to act fast if you want to keep Baurus alive, as several Mythic Dawn agents will appear and attack to aid Cameron. Raven Camoran holds the Mythic Dawn Commentaries 4 volume; locate his corpse and retrieve the book once the battle is over. Be sure to take the Sunken Sewers Key as well.
Only follow these next directions if you have a good amount of lockpicks. If you do not have any lockpicks, follow the quest marker on the compass at the bottom of the screen to find your way out. Just be sure to have 'The Path of Dawn' set as your active quest.
Head through the gate used by Raven to enter the sewers and climb up the steps there. Make your way through this area until you reach the Talos Plaza Sewers entrance. The Sunken Sewers Key will unlock the door here.
There are likely enemies in this next area, so be cautious. Look for the Turn Wheel by the fire and activate it to open the door on the west side of this room. Head through the door and up the steps to the left. In this next room, follow the passage on the east side. Move straight through this room, open the gate and then continue moving south down the next large area.
Next, head through the passage at the end of the way and use the door at the south end of this room to reach the South West Tunnel area. In this room, head straight to the door to the Temple Sewers across the way. Activate the Turn Wheel off to the right once you're through the tunnel and proceed through the gate that the wheel opens
Move through the room northeast of your current location. Cross the bridge and follow the series of rooms that you come to until you reach the end. Look for a Turn Wheel at the bottom of the stairs and activate it to open the gate in the circular room. Move down to the bottom level of the circular room and start down the newly accessible tunnel. Look for another Turn Wheel on the west side of the room at the end of the tunnel and activate it.
Head through the gate that the Turn Wheel opens and follow the tunnel. Move down to the lower level of this area, and follow the path up. Head through the open gate here, and take a right in the next room. Follow the path here and climb up the stairs to find a ladder leading into Amantius Allectus' Basement. The way to Amantius Allectus' Basement may be locked. If it is and you don't have any lockpicks, unfortunately you're out of luck unless you can scrounge some in the sewers. If you do have a limited number of lockpicks, be sure to save your game before attempting to unlock the ladder. Once you're through, get out of the basement and exit out to the Imperial City's Temple District.
Return to Arcane University and speak to Tar-Meena. She explains that Mankar Camoran hid a message within his writings that provide directions to the Mythic Dawn shrine. By deciphering the hidden message and locating the shrine, one would be considered worthy of joining the Mythic Dawn cult. Tar-Meena needs time to study the texts; if you return and speak to her a day later, she'll have deciphered the message. You can study the books and try to decipher the hidden message yourself, however.
Combine the first letter of each paragraph in the order they appear across the four Mythic Dawn Commentaries volumes to discover Mankar Camoran's secret message.
Each Mythic Dawn Commentaries volume is also a skill book, so each one to gain a skill level for each school of magic.
To decipher the hidden message, all you have to do is take the first letter of each paragraph and put them all together. Pretty simple, isn't it? Mankar Camoran's expectations of those he considers worthy must be fairly low. By taking the first letter of every paragraph across the four volumes and putting them together, you would get the following string of text: GREENEMPERORWAYWHERETOWERTOUCHESMIDDAYSUN. This string of text with spaces added is 'Green Emperor Way Where Tower Touches Midday Sun.'
Leave Arcane University and travel to the Imperial City's Palace District, which is the Green Emperor Way mentioned in the message. While standing at the bottom of the steps that lead up to the entrance of the palace, turn right and to spot a small tomb. This is the 'Tomb of Prince Camarril.' If the time is not near 12:00PM, press the Back/Select button and wait the amount of hours needed to advance to midday.
A map of Cyrodiil revealing the location of the Mythic Dawn shrine appears on the side of Prince Camarril's tomb in the Imperial City's Palace District from 11:30AM to 12:30PM each day.
Stand by the front of the shrine (the side with the vine hanging from it) and wait until the path is revealed. The symbol should light up at around 11:50AM, and disappear at 12:30PM. When the symbol appears, approach the shrine and press the A/X button when prompted. It is a map of Cyrodiil that shows the location of the Mythic Dawn shrine. Not the best place to put a map with directions to your top secret cult hideout, now is it?