Best Friend Forever

Best Friend Forever is a assignment featured in the Battlefield 3: Back to Karkand. Completing this assignment unlocks the FAMAS for the Assault Kit and it will be able to be used on any further multiplayer matches on any map in the game, rather than just the Back to Karkand maps.

The assignment right after Best Friend Forever is the Professional Russian assignment, which unlocks the L85A2 for the Assault Kit.

Criteria
To accomplish the assignment, players must attain ten revives with the defibrillator and ten heals or squad heals with the medkit after downloading and installing Back to Karkand.

Tips for Unlocking

 * The defibrillator is unlocked once the player has attained 4,000 XP in the Assault Kit. The player can equip it by pressing the right button on the D-pad (default on Xbox 360 and PS3) or by scrolling down three clicks on the mouse wheel or hitting the "4" key (default on PC).
 * The defibrillator is used by pressing the fire button (default right trigger on Xbox 360, R2 on PS3, LMB on PC) on downed allied players or squad members.
 * Downed players have a heartbeat icon above them that fades away until they cannot be revived. This time is usually just about enough for a player to get back to the spawn screen after dying and can vary by server. The heartbeat icon also appears on the minimap, to aid players in finding downed allies in their vicinity.
 * Getting revives with the defibrillator can be easily attained on primarily infantry-based maps like Operation Métro, Grand Bazaar, Damavand Peak, and Seine Crossing.
 * The medkit is unlocked by default for the Assault kit. It is thrown out in front of the player when they select it (default left button on D-pad for Xbox 360 and PS3, scrolling down two clicks or pressing "3" key on PC).
 * Players with a plus sign above them in the minimap and HUD are injured and can be healed by throwing a medkit near them. Players can also press the spot button (defaulted to back/select on Xbox 360 and PS3, "Q" key on PC) to call out to a fellow medic to request for healing. These players will have a flashing plus sign above them and on the minimap, as well as their soldier in-game requesting to be healed.
 * Depending on how injured players are, the healer can receive multiple heal or squad heal bonuses per player, up to a total of around 25 bonuses per life, to prevent boosting.
 * Throwing out a medkit in highly contested areas is a great way to get this criteria very easily, such as the various choke points on the maps stated above.