How to make spells' "ground" effects

Hey! I wanted to know how to make the “ground” or spell circle or whatever you call it, effects, similar to this the Circle(play the game) at the foot of the magician, made by effectronica, i tried searching their blog but unfortunately they don’t teach :), and the breakdown isn’t much help to newbies >< so i was wondering how to make one. Thanks in advance to all who could help!

You could make a particle system and attach it to your player. Then set it up to spit out particles upward in a circle around them. Unity - Manual: Particle systems has the basics, but if you play around with the particles, you can get some pretty neat effects.