When characters are turned to sparkly, shiny crystal versions of themselves.
In the two-parter season premiere "The Crystal Empire," the main six, Spike, Princess Cadance, and Shining Armor are shown to be crystallized by the effects of the Crystal Heart, although only temporarily. The crystal ponies are assumed to permanently stay crystallized as long as positive feelings are kept high for the Crystal Heart.
The following tags are aliased to this tag: cr.
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