Hallo 2 anniversary is going to contain a story segment that will link to Halo 5. At comic con 343 industries explained details about the game but also mentioned that a terminal in the game will have a motion comic with scenes form the Halo 5 Guardian. The scenes will focus on the Arbiter who was introduce in Halo 2 and seems to have become a fan favorite ever since.
Article:http://www.siliconera.com/2014/07/24/halo-2-anniversary-will-contain-extra-story-connects-halo-5/
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