The Necromongers are another elder race that seek a higher level of existence, a form of death, in a place called the Underverse. They plan on taking everyone with them so they travel from planet to planet, decimating the populations in the name of their religion. They are led by the Lord Marshal, who captures Riddick and learns that the two of them share both a past and a future.
http://en.wikipedia.org/wiki/Necromonger
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The Necromongers are another elder race that seek a higher level of existence, a form of death, in a place called the Underverse. They plan on taking everyone with them so they travel from planet to planet, decimating the populations in the name of their religion. They are led by the Lord Marshal, who captures Riddick and learns that the two of them share both a past and a future.