Character creation:
Honestly, this is fantastic. The character sign provides flavor, and the size of the stat die being determined by the stat value is a nifty concept. I also appreciate that there are no specific character classes. The emphasis on traits and spells makes this feel more like Skyrim or even Valheim, and I appreciate the flexibility this gives to any character build. This would be an easy system for a new GM to run.
Note: Which die (DD/HD/XD/CD/ID) is associated with which stat could be clearer -- I could only find that information on the character sheet.
Composure: I like it as a concept, but I think you may be using it for too much. It seems like it's supposed to reflect morality as well as level-headedness. This might be alright, except that so many things cause a character to lose Composure. If I was blasted in a fireball because the Wizard lost control of his spell, and spattered by gore during combat, that should shake me up, but it should *not* affect my moral character. If Composure wasn't so hard to regain, and the penalties (death outcome, etc) for low composure not so severe, it might not be a problem. Consider adding a "shaken" mechanic or finding some other way to separate the two concepts.
Note: The Death Table makes it seem like Composure values can go into the negative numbers. That's cool, actually, but you could make that a bit clearer in the section on losing composure. "Lose 100 Composure" when I have 10 composure meant (to me) that I would have zero, not -90.
Miscellaneous notes:
I love the Undeath mechanic. If you have time, I'd add three more types of undead here -- wights, ghosts, maybe draugr -- since you have space.
I like the level cap at five, and I *love* the selection of monsters (even though they're not all given stats). Very thematic.
Overall, I think this is a nice, light little combat sim. Not sure how well it follows the theme of "secrets", but maybe I missed something during the read through. I hope I get a chance to run it sometime!