Skill degradation
From FragoriaWiki
Skill degradation is a system that prevents players from using low-level abilities. Each skill has different levels (level they require). Let's overview it using Spark as an example:
There is a Spark skill that requires not much mana on level 1, and much more on level 8, while it's damage isn't that different and mostly depends on additional fire damage. So it becomes more profitable to use Spark level 1 then Spark level 8. To prevent this situation - skill degradation turns on.
Spark level 1 requires level 1 of character, and Spark level 8 - level 60 of character. So if you are level 60 and Spark level 8 is available to you and you are still using spark level 1 - it's effect will be lowered. The bigger is the difference between the skill level you are using and the skill level available for you - the lower will be the effect. So to have correct effect from skills you should be using the skill of corresponding level.
If there is no higher level for current skill - skill degradation wan't affect your skills, no matter what level difference is.