On October 9th 2008, it was announced that players with a copy of Resistance 2 in their Playstation 3, while having their PSP 2000 or 3000 connected via AV output to the television, will be able to play Resistance: Retribution with a DualShock 3 controller. This is a new, cross-link feature of both games dubbed PSP Plus. While PSP Plus is enabled, it has been reported that aim assist will be disabled and that players would be able to remap their controls to better use the extra inputs on the Playstation 3 controller. DualShock 3 rumble will also be supported.
Also announced was Infected mode which, by connecting R:R to R2 using a USB cable, going into the R2 options screen, and selecting Infect your PSP! provides an alternate story within the alternate history. While in prison for desertion, Grayson is recruited by Specter Lieutenant David LaSalle (from the R2 storyline) and is infected with a mutated version of the Chimeran virus, a different version of the virus that infects Nathan Hale.
While playing in infected mode, Grayson wears a Specter uniform and has glowing Chimeran eyes. Characters in the story will be aware of your Chimerian infection which will alter their behavior accordingly. He gets to use one of the new weapons from R2: the HE .44 Magnum, which fires explosive rounds that can be triggered remotely. He has regenerative health and no longer needs to look for health packs. He can breathe underwater, allowing him to reach hidden areas that he could not reach before. Also another whole class of Intel are hidden throughout the levels. Collecting all of the infected intel will unlock another R2 weapon, the Plasma Grenades. Infected mode lasts until you power down your PSP.
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