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In Incantation, power-ups work in pairs by creating combinations of power-ups that each have their own resulting spell. Know that the order matters, Fire Sparkle is different than Sparkle Fire.

You'll begin the game with dual crystals, a spell that creates two floating orbs that fly away laterally in opposite wave motions (a helix effect).

Combination Effect
Crystal+Crystal Dual helix shot.
Crystal+Sparkle Acorn; lobs a large acorn that explodes when it hits the ground or a target.
Fire+Fire Fire ball: shoots a fast flying projectile laterally.
Sparkle+Crystal Miniture Wizard: shoots a bouncing doll like figure that is similar to your character.
Sparkle+Fire Bomb, shoots laterally and bounces along the ground until it either reaches a target or explodes after several seconds.
Sparkle+Sparkle Magic Knife; fires a small dagger horizontally.