How do i add a glow around my character in the game

Hi guys,

Alex here again :)

I have a game character as a sprite with multiple animations within (animation for running, jumping...etc - each with 6-9 frames).

While running through the game, i collect some object that give the character invincibility. This works fine.

I want the character to get a glowing border around it while invincible, but i want to do this without having to change the frames in the animations (so without adding new animations) as i want a really nice glow. I know it will probably have to use opengl...or maybe not....not sure.

Ive gone through the list of effects and cannot find anything that creates a border around the character and makes it glow.

Can you guys help me with some tips on how to do that? maybe a combination if effects? or maybe an add-on?

Thank you.

Maybe some sort of shield around the character? Can anyone help with some examples?