Easy strategy for the boss (using greatsword) is to get behind him. When he uses the teleport to reset, you can usually manage him fairly well with knockback, and he'll just teleport to the same place over and over again. And enemies don't spawn behind you.
It's strange... the airplanes can all survive at least 16 'bird strikes' (that's when a bird hits the airplane) without crashing. Your average helo would probably loose control after one or two hit it. There needs to be a way to damage the planes.
I can understand your physics engine being inaccurate, but these things are freaking INCONSISTENT. You have something that works, and then you change something totally unconnected and BAM it disintegrates.
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