Well I managed to get to day 35 without dying. The lag is tremendous and it makes the machine gun useless. It seems near impossible to beat 40 with regular money. I was able to do it in sandbox with what seems like a reasonable amount of money (only had 31 repair men, 86 gunners, only three tower slots), so I think it might be possible, but only if you don't waste a single dollar. It deserves an impossible rank imo.
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