Pearl Dragon

Breeding
You can get this dragon by breeding an Ice Dragon with a Metal Dragon at the Breeding Mountain or Ultra Breeding Tree. Breeding an Ice Dragon with a Metal Dragon may also result in a Platinum Dragon.

Damage Calculator
To explain, when attacking with Ice, Pearl deals double damage against Earth and Plant, half damage against Electric and Ice, and no damage against Dark. When attacking with Metal, Pearl deals double damage against Earth and Ice, half damage against Fire and Metal, and no damage against Electric. When defending, Pearl takes double damage from Fire and MetalIce.

Trivia

 * This dragon as an baby can move the pearls on its tail around its body but as an adult it can move the pearls around its neck to form a 'Energy Shield' for a short time.