Terrigen Crystals are special minerals found in the Marvel Comics universe. They are known for their ability to activate the latent powers of individuals with Inhuman ancestry. When exposed to these crystals, a person undergoes a transformation that can grant them superhuman abilities. The process of transformation is called Terrigenesis. During this process, individuals are enveloped in a mist created from the crystals, which can lead to various outcomes, including the development of unique powers or, in some cases, physical mutations. The crystals play a crucial role in the culture and society of the Inhumans.