Co-op Objective is an online cooperative multiplayer mode in Uncharted 2: Among Thieves, that can be played with two or three players. Unlike competitive gametypes, players cooperate with each other against the computer.
Each match can be played on a difficulty level (Easy, Normal, Hard, or Crushing), which implicate player starting health, enemy weapon lethality and the types and numbers of enemies that will appear. Cash for medals and points are awarded for kills, collecting treasures and completing the mission. If a Co-op objective mission is played on Crushing, all enemy soldiers are replaced with skeletons. However, this does not affect the amount of bullets required to kill them as they still appear in their usual armour.
Like Co-op Arena, players are limited to 3 tries to per game regardless of difficulty, with a try being lost when all players are dead at the same time (not killed simultaneously). After losing a try, all players will restart at the last checkpoint, but after 3 failed tries, the game ends, though players are still awarded any cash/medals they have earned thus far.
Players that take too much damage are initially downed (though explosions are often instant death) and whilst in this state cannot do anything, as another teammate must revive the downed player within a timeframe (represented by a circled red gauge), otherwise the downed player will die.
Also present are Tetram soldiers who will grab players and begin to choke them to death, opening another timeframe (represented by a circled blue gauge) during which a teammate must free the grabbed player, however, this can be done from a distance with a gun, making it less of a threat. The grabbed player can also tap repeatedly to resist the chokehold for longer, giving teammates more time to reach him/her.
To avoid losing a try if one or two players are killed, the other(s) must either survive long enough for him/her/them to respawn, or reach a checkpoint causing all dead players to respawn instantly.
Points are accumulated for each player as they kill enemies. The quicker the succession of kills, the higher the point multiplier will go. Most enemies will also drop treasures, with each collected increasing the point multiplier by one.
There are three Co-op Objective missions, each take place in location featured in the single player campaign with multiple stages and unique short cutscenes and dialogue.
Fight to destroy a communication tower.
|I Told You I Was Hardcore!||If the player has the Drake's Fortune Multiplayer Pack and completes all three missions on Hard difficulty, this bronze trophy is awarded.|
|You Can't Break Me||If the player has the Siege Expansion Pack and completes all three missions on Crushing, this bronze trophy is awarded.|
|Masters of the Universe||When any of the three Co-Op objective missions are completed on Crushing, this medal is awarded.||$5000|
|Back to Back||If any of the three Co-Op objective missions is completed on Crushing with only two players, this medal is awarded.||$5000|
If a Co-Op objective mission is completed in less than fifteen minutes, this medal is awarded.