Primarily serving as a source of information, Mr. Jigsaw is one of the most powerful allies avaliable to Lazarus. He knows about the movements of the Malfeans and Grandmother, the history of the Shadowlands, and how to turn a Spectre into an Orphan-Grinder, among other things. He offers this information for favors and information in return. He also seems to be able to resist and hide things from the Spectral hive-mind.
It is both his personality and appearance that make Mr. Jigsaw stand out among his contemporaries. Unlike the rage-filled, primitive nature of most other Spectres, Mr. Jigsaw is unfailingly polite and refined. He never loses his cool, and is able to wheel and deal with any informant to get what he wants. He cannot disguise his naturally malevolent nature, however, making him extremely off-putting to ghosts and projectors that deal with him on a regular basis. Even more bizarre is his form. At a glance, Mr. Jigsaw is a man dressed in an impeccable white suit and fedora, with a black tie for the suit and black band on the fedora. It doesn't take long to realize that the suit is not filled with a solid body, but rather an oily black ooze in the shape of one. Most disturbing is his manner of speaking. When he talks, a cadaverous face pushes its way to the surface of the ooze where his face should be; the voice is that which belongs to the face, be it a small girl or an elderly man. When he is done, the face disappears back into the ooze.
Challenging Mr. Jigsaw directly, and especially with violence, is not a good idea. If offended or threatened, Mr. Jigsaw removes his hat and bows. His body from the waist up splits up the sides, revealing a gaping maw and a black tentacle-tongue which previously served as his tie. The tongue grabs the victim and pulls it into the maw, after which the mouth shuts and Mr. Jigsaw resumes his normal appearance. The things he swallows become part of his being, both in the form of a face and voice for his physical form, and another personality that he can use to confound the hive-mind. To resist Mr. Jigsaw, or his help, is an exercise in futility.