There are a total of 145 ranks. After rank 45 (Colonel), Colonel service stars are introduced, requiring 230,000 points for each subsequent Colonel rank. In comparison to Battlefield: Bad Company 2, Battlefield 3 has 10 times the unlocks over weapons, weapon attachments, gadgets and an unlock tree for vehicles alone. In addition, unlocks are more spread through the ranks, instead of ending after rank 22.
There are also Ribbons and Medals (similar to BC2's Pins and Insignias) with examples being Rush Ribbon, Shotgun Medal, etc. Service Stars are added to the player's weapon skill badge, kit, vehicles, and their overall rank, and allow for further promotion.
Classes in Battlefield 3 have been tweaked in relation to their roles from Battlefield: Bad Company 2, whilst still utilizing the same four class system.
Assault - Takes on the role of the Medic, similar to the Medic] class in Battlefield 2. Features an assault rifle as a primary weapon yet Medkits and Defibrillators for reviving and healing players, instead of ammunition boxes. Players can also opt for using a grenade launcher instead of some medical equipment however.
Support - Replaces the Medic from previous Battlefield games. Features Ammunition boxes and a light machine gun, ideal to suppress opposing players with the new suppressive fire mechanic which causes them to have no health regeneration and debilitating visual effects.
Recon - Retains role for engaging combatants at long ranges. The speed of scoping is reduced, requiring players to hold their breath in order to fire an accurate shot. Claymores and C4 have also been given to Support. Recon players are equipped with either a bolt action or semi-automatic sniper rifle. The kit now has access to the T-UGS motion sensor as well as the Spawn Beacon and Micro Air Vehicle.
Maps and Gametypes
There are a total of nine multiplayer maps featured in the base game with expansion increasing the total to twenty-nine maps. The locations of the multiplayer maps, like the campaign, includes Europe and the Middle East. More specifically, the game takes place in the cities of Paris and Tehran.
All gametypes from Battlefield: Bad Company 2 return, with Team Deathmatch being a new addition. There are a total of five gametypes in the base game, with expansions increasing the total to thirteen. Gametypes in expansions can only be played in that expansion's respective maps. Attack Helicopters and fighter jets are available in Rush as well as in Conquest and Conquest Assault. Hardcore and infantry-only options are also present (Note that the The infantry-only option only removes all classes of vehicles except transports, such as the HMMWV, RIB, etc.)
Weapon unlocks obtained from the co-op campaign are carried over to multiplayer. There are currently over 50 weapons to unlock, and also each primary weapon contains three attachment slots ranging from foregrips to optics. Weapon accessories are unlocked per weapon unlike in Bad Company 2.
Unlocking an attachment such as a Red Dot Sight while using one class still enables it for every other class that can use that weapon. However, the attachment will not be available on other weapons until it is unlocked. DICE has stated that it takes over "100 hours" to unlock everything for a kit in Multiplayer.
There are two multiplayer factions: the Russian Army and the United StatesMarine Corps. Like with previous Battlefield games, their default kits are equipped with faction-specific weaponry until others are unlocked.
Destruction 3.0 - With Frostbite 2.0 comes the Destruction 3.0 engine. This engine allows debris that can injure/kill players and micro-destruction, as well.
Suppressive Fire - Firing at enemies causes their health regeneration to stop and reset, their accuracy drops, and the edges of their screen become blurred. While suppression is most effective with the Support class and their LMG's, any weapon is capable of suppressing an enemy.
Disable Vehicles - Vehicles can now be disabled before they are destroyed. This makes land vehicles immobile (but turrets are still operable), while air vehicles become extremely difficult to control. When a vehicle is disabled, it can be repaired, but will also slowly bleed health.
Vehicle Health Regeneration - Vehicles now slowly regenerate health when damaged. Repairs from an Engineer are still far more effective, and regeneration is cancelled if the vehicle is disabled. Vehicles will start regenerating when they are under 75% health (server option).
Assignments - Introduced in the Back to Karkand expansion pack, players must complete a series of tasks for each assignment to unlock either new weapons, camos, dog tags, or other assignments. Players can fulfill the criteria for any assignment on any Battlefield 3 map, as opposed to just the maps of the expansion the assignment came from.
Customization - Allows players to change the appearance of their soldier and weapon as well as the option to customiz weapons with unlocked attachments. DICE claims that there will be years worth of unlocks and specializations to use in multiplayer.
Specializations - Function similar to Battlefield: Bad Company 2 counterparts. Give players specialized bonuses depending on each specialization.
Scope Glare - If a player is using a high power scope (6x and above) and is aimed in the direction of another player, a visible glare/glint shines off of the scope. This was added to balance the addition of the prone position.
Colorblind - A feature originally exclusive to PC players that changes the colors of teammates, squadmate, and enemies to better differentiate between them and adds a black border.
Renting Servers: Allows players to rent a Serverand customize it's gameplay settings.