Attributes and elements are different.
For example attributes are destruction, gravity, Death,life etc..
Attributes are used to amplify and strengthens the elements and the user.
where as elements are Fire , water, wind earth, thunder, ice etc...
There will be cases where both attributes and elements a person has will be the same.
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(Author note): Mutated elements, Are elements which have different characteristics, For example Raven's flame. A normal flame would be a red colour without any characteristics.