Yet again told from the perspective of my fantasy self.
The story nor the front of the letter are needed to solve the puzzle.
Just like before, the story continues but the puzzles are unrelated.
A few months later...
Today the party and I had woken up, only to quickly see that Astrid had not come down for breakfast or invited me to make it. Soon we found ourselves at her room, knocking on the door, with no reply. Eventually I resorted to lockpicking my way in, but was surprised to see an empty room, the window at the back wide open.
The current theory is that she ditched us and ran away, which is extremely obvious. Moments like these are when I like to think I'm the smartest one here. I soon excused myself from mealtime and headed to the riverbank and try to collect my thoughts.
"Now why would she leave us? She seemed to at least enjoy my company..." I pondered. But that's when I heard it. Once I started to sit down, there was a peculiar crunching sound coming from my robe. I reached into an inside pocket, only to find a lock of bright orange hair - neatly wound and braided - attached to a piece of parchment. These were undeniably from Astrid. I've met nobody else with papyrus this ancient, let alone anyone with this shade of hair.
Here's what was on the paper:
My dear friend, Please forgive me for leaving so suddenly. I am not who you believe I am. I've wanted to discuss it with you for the longest time, but I recently discovered that you are not the only one snooping through my texts. I fear that our party members may resent me if they discovered who I am. Therefore, I ask you to please keep this message secret from the others. Please do not attempt to find or follow me. It is suicide to do so. I do not need more blood of my companions filling my footsteps. You should find enclosed something to remember me by. It may also help you survive should you attempt to follow me. Truly, Astrid
What is Astrid's secret?
Hint the First
That second D-word might help you...
Hint the Second
The equation is a key to a fine cipher...
Hint the Third
Let's hope her absence doesn't leave any lasting damage...
Hint the Fourth
I might just have to spell it out...