In Skylanders Ring of Heroes each of the characters belongs to one of 10 elements and there is a correlation between the different elements. Each element is strong, weak against another and during a battle you can get an elemental advantage in the form of extra damage if your element is stronger than that of your foe. Below is a list of the elements showing you what each is strong and weak against.
Undead Element
Strong: Life, Earth
Weak: Magic, Fire
Magic Element
Strong: Undead, Air
Weak: Water, Tech
Fire Element
Strong: Undead, Air
Weak: Water, Tech
Air Element
Strong: Life, Earth
Weak: Magic, Fire
Life Element
Strong: Water, Tech
Weak: Undead, Air
Earth Element
Strong: Water, Tech
Weak: Undead, Air
Tech Element
Strong: Magic Fire
Weak: Earth, Life
Water Element
Strong: Magic, Fire
Weak: Earth, Life
Light Element
Strong: Dark
Weak: N/A
Dark Element
Strong: Light
Weak: N/A