In Skylanders there are now ten basic elements. These include:
Each Skylander belongs to one of these elements. The element of each Skylander can easily be determined by looking at the base of the figure.
The bases of the Air Skylanders feature puffy clouds.
The bases of the Dark Skylanders have swirling black clouds.
The bases of the Earth Skylanders have mounds of dirt with random crystals sticking out of the ground.
The bases of the Fire Skylanders are pure flames.
The bases of the Life Skylanders are a pile of leaves.
The bases of the Light Skylanders have a white and gold sunburst pattern.
The bases of the Magic Skylanders feature a bronzed half-sphere with various “magical” symbols.
The bases of the Tech Skylanders are a stack of gears.
The bases of the Undead Skylanders have a giant skull.
The bases of the Water Skylanders feature splashing water.
Aside from the base design, each element is also associated with a symbol.
These symbols can be found on the Skylanders packaging as well as in the game.
Throughout the game there will be different areas in which different elements are stronger or even areas which can only be accessed by Skylanders of a particular element.
For this reason it is recommended that you have at least one Skylander of each element in your collection. While this is not necessary to complete the basic game, having at least one Skylander from each element will allow you to get the most out of your Skylanders experience.
In Trap Team, not only do the Skylanders have elements, but each of the Villains will be associated with an element as well. This is an important note because you will need a Trap of the proper element in order to capture these Villains.
While the eight basic elements provided a great base through the first three Skylanders games, the fourth (Skylanders Trap Team) game shakes things up a bit.
During the first three games, Skylanders were always created in multiples of eight (one for each element). In Trap Team, this rule no longer holds true. This is due in part to the addition of two new elements (Light and Dark).
You can read more about the new elements in these articles:
Light? Dark? Expansion Packs? – Are We Still Talking About Skylanders?
Question Marks No More: Two New Elements – Fully Explained
The Dark and Light Elements carried over into Skylanders SuperChargers, but they are still considered minor Elements.
This simply means that while we're seeing at least 2 Skylanders in each of the eight original Elements, there is only 1 Light Skylander and 1 Dark Skylander.