When you have the creature unlock in your bestiary the message will say, instead of "unknown", the difficulty of the creature. This can be Trivial which is the easiest, Easy, Medium, Hard and Challenging. With this information you can get an idea of what monster is boost based on the direction the spell is telling you to go and the class. For example, if it says challenging instantly you know its a Soulwar creature because there are only challenging creatures in Soulwar