Just as the title says, this is a video guide on how to navigate and 100% clear Cathedral of the Sacred Blood in under 50 minutes or less. No rush needed, just play normally and use guide as a reference, pause and rewind when you get lost or unsure where to go.

https://www.youtube.com/watch?v=QIo_UEnTLsM

1. 0:00 - 1st Rotten Mistle
   
2. 5:45 - 2nd Rotten Mistle
   
3. 9:02 - Artifice Tower Mistle
   
4. 10:25 - Outlook Tower Mistle
   
5. 14:37 - 3rd Rotten Mistle
   
6. 18:25 - 4th Rotten Mistle
   
7. 19:55 - Gated Room Mistle
   
8. 21:10 - 5th Rotten Mistle
   
9. 23:17 - 6th Rotten Mistle
   
10. 27:03 - Argent Wolf Berserker
    
11. 30:14 - Cathedral Perimeter Mistle
    
12. 32:03 - 7th Rotten Mistle
    
13. 39:23 - Inner Tower Mistle
    
14. 39:37 - 8th Rotten Mistle
    
15. 40:55 - Trials of Blood
    
16. 42:55 - 9th Rotten Mistle
    
17. 46:13 - Cathedral Front Mistle

1. Isis Vestige Part B (Trials of Blood) at 1:41
   
2. Isis Vestige Part C at 12:39
   
3. Gustav's 2nd quest item at 14:47 (if you have finished his 1st quest before)
   
4. Shoddy Key at 34:35
   
5. Isis Vestige Part E at 37:58
   
6. Isis Vestige Part A at 40:45
   
7. Ornate Key at 46:13 (after 9th Rotten Mistle)

Notes : These items along with other items placed in the world will only appear for the host to pick up. Because I'm not the host so they don't appear for me to pick up. If you play singleplayer or be the host, you should have no problem picking up these items.

Tips :

• Use chemical light to create your own landmark at T-Section or places that have multiple paths, this helps you remember where you have gone before and not running in circle and don't know where to go.
  
• The Trials of Blood where you pick up Isis Vestige Part B can be skipped if you manage to run back to the Mistle. Enemies will despawn and you will still have the Vestige. You don't need to go here if you don't intend to pick up the Vestige.
  
• There is a Trial of Blood after you slide down the ladder at 33:31. Don't trigger it here as it is a bad spot to fight. Tight space and falling down the edge of the path will make your fight harder and frustrated. Running back to Mistle is possible but tricky since the enemies can teleport themselves to catch up with you. You can prepare and trigger it later on at 41:10. This Trial of Blood is optional and can be skipped.
  
• Be patient, have fun, enjoy the atmosphere and scenery here. The Cathedral is designed to get lost as mentioned in the story, so its doing a damn great job at it. However, the lack of noticeable landmarks for the players to navigate is undoubtedly a downside and frustration. Just use chemical light to mark your way !