I got an idea, a Beast mode.
What about a mode where one player is overpowered (Beast), like driving a train or 18 wheeler long vehicle. Other players try to destroy him, like Ants or something, but of course, it's crazy hard. The Beast takes up a lot of space, you have to jump over him, drive on the ceiling in the tunnels, very risky stuff.
Similar to mechanics in Split/Second, there was one mode where you were overtaking huge 18 wheelers, while they were dropping bombs on you. There could be even some competition between the other players, to get the highest score = to not get killed, to survive for longest time, to cause the most damage to the Beast, etc.
A little bit similar concept is in Evolve, 4 players going against one monster.
So, the Beast mode would motivate players to cooperate against the Beast, but they will be given points based on individual performance. However, if they destroy the Beast, they will get much more points, so cooperation would be rewarded as well.
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