Spawns when you unlock the Suspiciously Angry Vault. In order to do this, you must find three 'keys' in the area (shaped like a sphere, a cube, and a star) and click on them to activate them. You can then interact with the Vault.
Level scaling: Most NPCs will scale with the Hunter's level, within the constraints of their level range. Hunters can tame regular NPCs up to 2 levels higher than them, but can only tame elite NPCs of the hunter's level or below.