 Perfect Dark is a first @-@ person shooter with elements of <unk> games . In the game 's campaign mode , the player controls Joanna Dark through a series of <unk> levels collected together into missions . Each level requires the player to complete a certain number of objectives , ranging from <unk> oneself to hacking computers , collecting objects , and defeating enemies , among others . Players can carry an unlimited number of weapons and almost all of the weapons have two firing modes . The levels in Perfect Dark have no checkpoints , meaning that if Joanna is killed or fails an objective , the player has to start the level from the beginning . Every level can be played on three difficulty settings and several aspects , such as the enemies aggressiveness and the number of objectives that must be completed , among others , can vary in function of the chosen difficulty . Two players can also play the campaign co @-@ <unk> or through a " counter @-@ operative " mode , in which one player controls the protagonist , while the other controls enemies throughout the level , attempting to stop the first player from completing objectives . 
