Portable first-person shooters generally suck. The controls are too limited, the screens too small for fine detail, or the stories aren’t more than simple set dressing for an egregious bullet and blood ballet. Killzone: Mercenary does not feel like a portable first-person shooter.
The PlayStation Vita is a good, powerful handheld machine that’s run some piss-poor first-person shooters. After rushed, clunky Resistance and Call of Duty shooters, the system will get a Killzone in September. It merely needs to be mediocre to improve Vita FPSing dramatically.