Some quest tips in Aion Online

In the event you press the letter J on your keyboard and select the quest you are currently proceeding, you will notice NPC and MOB names which are highlighted in blue
This tells you that you are able to find more information out about this MOB or NPC. If you open the quest, and select the MOB in need to complete the objective, in most cases you are able to click the locate button and then an area will be marked on the map where the mobs tends to patrol. Some mobs will not be locatable, but most can be found with a little searching.