The new first-person shooter is built for Vita using the same engine that powered Killzone 3. It will feature missions taking the side of both the ISA and the Helghast as players take on the role of a mercenary completing missions for the highest bidder.
Players will be rewarded with new weapons and equipment for completing missions, which can be used to customise their loadout.
Sony also revealed a new trailer for Assassin's Creed 3: Liberation on Vita, showing how touch control will be used both for combat and movement. The touch to kill feature allows players to tap enemies to quickly target them, while the rear touch panel can be used to row a canoe down a stream.
No release date has been announced for Killzone: Mercenaries.
Assassin's Creed 3: Liberation will be available worldwide on October 31 alongside the Xbox 360 and PlayStation 3 versions of Assassin's Creed 3.
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Watch the trailer for Assassin's Creed 3: Liberation below: