Your first puzzle in the game will take place in the tower you need to investigate for Vargas, right outside of the prison. This will be in a room with a bunch of Roman numerals and Zodiac symbols on the wall. Before doing anything, you need to inspect a sun and moon symbol on the wall by the door. Doing this will have you look at some letter, which will point you in the right direction by checking out the Sagittarius and Scorpio Zodiac symbols. These two symbols will have Roman numerals attached to them (X and II, respectively). Both of the stones with those numbers don't do anything on their own, so add them together to get the Roman numeral for 12, which is XII. Inspect that stone to solve the puzzle and continue the story.
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