An element is a kin's magical property which determines which type of offensive advantage it will have over the opposing kin.
There are 5 types of elements: Fire, Water. Stone, Metal and Wood. For each element, with will have certain strengths and weaknesses over the opposing kin's element, similar to a game of Rock/Paper/Scissors; an element may be strong against one, but weak against another.
Each element is attributes to a specific status:
Fire element kin have wither status attacks;
Water for sleep;
Stone for paralyse;
Metal for confusion;
And Wood for poison.
Most kin only have one element, but it is possible for a kin to have two or more elements.
How to determine a kin's element
For most kin, you can determine their element by what status effect their attacks cause. A kin with the Wither skill will most likely be a Fire element, so on and so forth. But there are a few special cases where this is not a viable option, (Such as with Hey Doge, who has it's own unique attack animation). Heal moves are not element specific, so they do not count as a viable element determiner.