The Codex pages — Leonardo da Vinci's translations of Altaïr's manuscript, the hidden history of the Assassins embedded in the scientific and philosophical language of the Renaissance. The past written in blood is both the Auditore family's death (the ink of Ezio's education) and the Assassin Brotherhood's actual history, the record of violence and purpose that the Codex encodes. The ink is the surface. The blood is what the ink is covering.