Most, but not all, panthara require a trick to tame. Farm up some Fresh Talbuk Meat which is drops rarely from talbuks on Argus; approach your target; throw a Freezing Trap; Feign Death to lose aggro (this is essential for the meat to work); throw the meat directly on top of the panthara; tame quickly! Panthara that do not require this trick are Naroua, Sabuul, and the Shadow Stalkers in The Seat of the Triumvirate dungeon.
At the back, behind Naroua. Only one seems to be present.
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.