Here is the full list of all 10 An Assassin in Orlandes achievements.
Find all the images in the book
Find the ultimate ending in Classic Mode
Find the ultimate ending in any mode
Find the best armour
Find the best weapon
Roll 3 ones in a single roll
Find Kari
Roll 3 sixes in a single roll
Find Eltane's castle
Find Medius the Cannibal