The LightCore Skylanders were first introduced in Skylanders: Giants. When placed on the Portal of Power, a portion of the LightCore figure will actually light up (no batteries needed).
The LightCore figures will be posed differently than their base figure. This is the easiest way to tell them apart without placing them on the Portal.
Most LightCore figures have not been hard to find. In fact, you can often find them online at discounted prices. However, the final character, LightCore Hex has yet to be released in the US. For a limited you can get your LightCore Hex for free by pre-ordering Skylanders SWAP Force.
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