TIPS 1. Firstly and most importantly make sure you collect ALL “codex pages”. Whenever you see one on your map, GET IT. I won’t tell you the reasoning behind it, as it is story related, but make sure you collect any that you encounter, preferably all of them, because at the end of the game, to gain access to the final section, you’re going to need all 30. Fortunately, if you don’t have them at that point in the game they will all get revealed on your map and you will be sent off to get them, so you can wait until then to find them, although it will be a lot off your mind if you collect them as you play. Since they give bonuses such as extra health and upgrades to the hidden blade, if you give enough to Leonardo Da Vinci, it’s worth your time to get them in any case.