From Destinypedia, the Destiny wiki
Cryptoliths are Hive structures created and utilized by Xivu Arath, the Hive God of War, in order to corrupt the enemies of the Last City and turn them into mindless and enraged champions for her army known as the Wrathborn.
Like most Hive architecture, Cryptoliths are partially biological, growing like plants wherever they are seeded. When dormant, they lie still and are mostly hidden below ground; when activated, they rise up and begin glowing, and various pieces of their outer shell begins to move.
List of appearances