Fun fact: Providence actually has a symbol hidden in the particle textures, as implied by the filename (texArcaneCircleProvi)
This is the particle used in the Stone Golem laser charge animation. A simplified version is used by both Lesser and Greater Wisps charging their attacks. Pretty neat.
Mithrix has a particle symbol too (texArcaneCircleBrother,) that's used by the Tank Chimera. It's just the banner design from the Bazaar, but more polygonal.