The story mode within Metal Gear Solid: Portable Ops has been removed, and a new single player mode has been added called Infinity Mission, where the player must go through randomly chosen maps, looking for the advance point within the level, using the surround indicator to help them. This adds some extra difficulty, because the surround indicator could show an enemy, or the advance point. Within this mode, there are also kerotan, which make a small croak sound, as well as briefly showing on the surround indicator with every croak. The game places an emphasis on online gameplay, with the modes from the original being used with their + counterparts, such as "Cyber-Survival+" and "Infrastructure+". During online gameplay, rookie players will have a rookie mark, reducing the damage they get, and increasing the damage they give, making online gameplay easier for less skilled players.