Just little sketchdump with small concept :3

I think unicorn magic can be different forms.
For example:
• Cloudy smoke. Looks like a graceful curly shining cloud. Slightly blurry but still has relatively clear shape
• Blurry light. Looks like very blurry, not having a clear shape with weak density
• Flame impulse. Looks like true fire but NOT burns
• Shiny rings. Looks like…shiny rings :D They fly very quickly from base of horn to its tip and disappear, narrowing to point
• Flowing smoke. Looks like dense haze that flows from slits of horn. Characteristic for smooth horns with slits along
• Shining slits. It looks just bright light from slits. Characteristic for horns with a spiral notch
• Lightnings. Looks like lightning bolts around horn. And one moment: Tempest DOESN'T have that form, her magic just poorly controlled. Lightning form of magic is fully controlled.
• Shiny hoops. Resembles rings but it doesn't appear side by side, it looks as one or two hoops sometimes double and / or with rays.

Such things. These are not all the forms that I can imagine in unicorns, but relatively basic.
If anything, you can take this idea for yourself, I don't mind :3