Made of leather with plaited tiny nuggets of copper woven into the braids. The bullwhip begins to glow with yellow light by a spell whenever it comes into contact with undead beings. It protects the user by radiating a power that is abhorrent to them. It increases combat prowess when used in battle against the undead.
Lone Wolf can acquire a Bullwhip from Halgar in The Dungeons of Torgar, if he takes the Pirsi route, visits the watchtower, and doesn't have the Magnakai discipline of Invisibility. In this route, Lone Wolf is disguised as an Eruan Pathfinder seeking directions to partisan leader Sebb Jarel. Halgar (who is Sebb Jarel's brother) quickly deduces that Lone Wolf is not who he claims to be, and attacks. Lone Wolf is forced to fight. If he wins, he can acquire the Bullwhip afterwards.
If Lone Wolf carries the Bullwhip, the partisans he's seeking to contact will recognize the weapon. Since they also know Halgar would not have parted with it willingly, they will attack. This forces Lone Wolf to go to the Isle of Ghosts, where he encounters Roark, Tagazin, and the ghosts of Cener druids. The Bullwhip is capable of hurting the ghosts; if Lone Wolf does not have it (or the Sommerswerd) it is much harder for Lone Wolf to survive the encounter.