Furbearing your ninja efforts
The Forsaken World Gold learns the ability to control spirit summons, and is the only pet controlling class in the game. Your group has two options now, you can either charge forward banners held high into battle taking down the lepharists in packs of 2-4 or you can put Assassins to shame and sneak around the side. For your first run I would probably advise the middle path, nothing more frustrating than a Spiritmaster pet furbearing your ninja efforts and pulling fifteen mobs.