specific role to better suit the player's needs in battle. There are 7 classes in total, in which the player can mix and match a main and sub ability according to their playing style, and can switch abilities upon death. There are 15 weapons available to the player, most of which cannot be used until the player reaches a certain rank. Two of these weapons are secondary firearms, and a further two weapons, the Boltgun and Flamethrower, are exclusive to the downloadable maps "Suljeva Cliffside" and "Arctower Landing". Players play as either the ISA or Helghast, with a few gameplay differences. The character model and respawn points, and the "lean and peek" cover systems were removed. Each class levels up with experience gained from killing enemies or completing mission objectives. With enough experience, players unlock new weapons and skills, as well as a new class. Each class has two badges, the Primary badge selects the class and their specified skill. The secondary badge has an extra skill for the specified class but can be swapped to create own custom class. Warzone plays out through dynamic matches where multiple game types are played in a single round. The game does not reset between game types, instead flowing between them, with the winning team determined by who wins the most modes. The game ships with five different game types including Assassination, Search & Retrieve, Search & Destroy, Bodycount and Capture & Hold. Online matches can connect 2 to 32 players, and they can group into six squads of up to four players. If an online match does not have a full 32 players, computer-generated "bots" can be added in to create bigger teams (but only in an unranked match). Killzone 2 also offers a clan system, which allows clans of up to 64 players to compete for "Valor Points", an in-game currency that clans can use to bet on tournaments. Players can also play offline against AIs with Skirmish mode and unranked online multiplayer, but there is no offline multiplayer mode for splitscreen players. Eight multiplayer maps are included on disc at release, but Guerrilla has released more maps as downloadable content. 6 more maps have been added to multiplayer since release via downloadable content purchasable from the PlayStation Store. Plot Two years after the attempted Helghast invasion of Vekta, an ISA fleet led by Colonel Jan Templar is sent to attack