The MP-9 is a submachine gun which became popular because of its high accuracy and mobility. The weapon was decorated with a red color scheme, which is associated with poisonous substances. Exchange your Soul Gems for the MP-9 Ruby Poison Dart! The MP9 is a submachine gun with an average rate of fire, but it deals high damage at close range. It was wrapped in transparent red hydrographics with a pattern resembling poison. The weapon was covered with a special liquid crystal coating which glows in the dark. Exchange your Soul Gems for the MP9 Ruby Poison Dart!