Aura Effect Critique

After playing Jump force I was inspired by their charge up aura effects, so I wanted to make an evil aura type of power up as one of my first effects.
I would love feedback on what I need to work on, something feels a little off personally but I don’t know what the effect is missing. Finding a hard time finding reference for aura’s for some reason
DarkAura
Here’s the particle on an animated character so you guy’s can get an idea of what I am going for:
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