Imagine the 18 wheeler as a huge worm like design, or like a train. Taking up shitloads of space, making it difficult for others to pass around.
Make one player overpowered, as in a train or 18 wheeler, make the others destroy him. Like... the crazy levels in Split/Second where you have to overtake 18 wheelers, or little bit like in Evolve, where 4 players hunt down one overpowered beast.
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