Lol to the matrix reference. I dont think it's a drawn game. A stalemate can also occur when both sides are trying to get into a position to attack. They set up pawns so they can move stronger pieces into better positions. Technically, nothing can occur until you have set up your attack plan. So the time between the Purge and the Losties crashed on the island was when both sides was setting up their attack. The pieces fell into place at that point and both side were ready to attack. So its not a drawn game, just a drawn out game. Every move they make takes a lot of time.
Ben is not going to kill Charles for three reasons. One, just like chess a king cannot capture a king. Second, Ben wants revenge for Alex a lot more than he wants to kill Charles. He wants Charles to suffer just like he is suffering over Alex. Thirdly, how much more satisfying is a victory (with any game that deals with multiple pieces) when you destroy the opponent by taking everything away from him. Both Ben and Charles have huge egos and simply killing each other would not satisfy them. Taking away little by little until one is on his knees begging for mercy is a better victory for them.

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