Well Demon Arrow and Devil Arrow are the same casting time, and Demon is (250%) while Devil is (350%). I thought they said in Q&A it had something to do with cast time, but duno for sure, dont think it is.
Also I think anti devils do take longer to shoot from book 1 to 3.
At this moment, we are not able to answer individually all the many questions that you, the users, may have however we are reading and considering, without exception, all of your opinions and questions.
In order to better fulfill this service need we will instead, post about every 1-3 days a Question and Answer notice.
This may be a small step but we hope it will be a great help and we hope that in the future you will be able to keenly feel the improvements in service planned.
****************** 2/7 Update
Q. In the Skill descriptions, you have the damage sections listed in this form ex:100-130 (150%). What do each of the numbers refer to?
A. The percentage (example being 150%) does not indicate extra damage, but is one of the factors considered when calculating damage and is a variable rate that users must pay attention to. Simply put, if the percentage is higher the rate of the skill may be slower but the damage will be higher. Conversely, when the percentage is lower, the rate may be faster but the damage is lower.