Battlefield bad company 2 onslaught mode?

I just bought battlefield bad company 2 onslaught mode and I don't understand it? Do you really kill other players online or is it a computer? Can somebody explain it to me.





Thank you.Battlefield bad company 2 onslaught mode?
Onslaught mode puts a squad of up to 4 players into a co-op missions against an army of enemy AI across 4 maps all while squads compete to obtain the best time on the Onslaught specific leaderboards against other squads

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