Can only be used by hunters in the Beast Mastery spec. Minimum level 39 in Shadowlands.
You must learn the skill to tame Gargons, which is taught by a Gargon Training Manual, a guaranteed drop from Huntmaster Petrus, a rare NPC that can appear in the Witherfall Ruin area of south-east Revendreth. It appears this manual can only be read at level 60.
Location & Notes:
Located in Halls of Atonement, Revendreth. Patrols the southern perimeter. Appears to phase out later in the zone quest chain and is probably unavailable for hunters who select the Threads of Fate advancement path.