Here is the full list of all 12 Ouroboros: Prelude achievements.
Collected 100 pieces of tinder.
Collected 100 flint stones.
Collected 100 steel strikers.
Collect 100 candles.
Collected 100 elixirs.
Collected 100 tinctures.
Collected 100 keys.
Get out alive.
Stay conscious for 1 hour.
Stay conscious for 2 hours.
Stay conscious for 3 hours.
Destroy the Count's work.