Beacon Hat (+15 Elemental Power, +30 Maximum Health)
When you reach Ice Break Atolls, leap directly across the icy chunks in the river to reach an Air Elemental Gate. Use an Air Skylander to open the gate and clear the course inside. You'll receive the hat as a reward.
Flower Garland (+10 Critical Hit %)
After battling the Missile Mauler at Fantasm Beach, you'll be near a Tech Elemental Gate. Use a Tech Skylander to open the path, then complete the course inside to earn this.
Asteroid Hat (+60 Maximum Health)
When you escape the first tank in Flooded Containments, you'll be near a Water Elemental Gate. Use a Water Skylander to open the way, then beat Mister Chompy inside to receive this.