2D Forcefield effect on gameObject

I'm working on a 2D pixel art platformer, and I want an effect for when my character get's "charged" up, he recharges his mana. I need some kind of like energy being given off around his outline, but I'm unsure how to do this. Just going in and drawing/animating it is not ideal as I would have to do it for all the different sets of animation there are, or I freeze the character and I don't want to do that either, so ideally it would be a coding effect. Any ideas?

 

What do you mean given off? I think that you could maybe use a particle system, but, I'm sorta unsure of your question. Could you clarify?

 

I can't really use Unity's particle system, because when I scroll the screen left/right etc the particles are all at different depths so they look all weird, the only way I found around that was to force each particle to the same Z but it's more trouble than it's worth so I roll my own particles.

But to answer your question, kind of like an old school pixel 2d effect, like energy coming off the character as they get charged up, could also be a halo hoop type effect rising from the ground.