The Stone Dragon is an NPC that appears in Dark Souls.
The Stone Dragon is a large four-winged beast with bristling fur, stony scales, and a damaged horn that resides near Ash Lake. It is said to be one of the few Archdragons that survived the war with Gwyn and the Lords for control of the world. The Chosen Undead can talk to it to join a covenant called Path of the Dragon, as well as sever its tail to obtain a Dragon Greatsword.