bowling balls because of size and inertia required when shot backwards should accelerate the karts. also slight(maybe not full weight) slowdown when shooting ahead to make gameplay more realistic. a bigger boost than normal may be preferred even. would integrate well with existing ai likely for visual appeal/functionality
STK does not aim to implement realistic physics. This can be discussed I guess, but for STK it should be discussed on the grounds of whether it improves the gameplay, and not on the ground of whether the laws of physics are respected
Sorry, I'm not convinced it would fit well with the gameplay. Backward bowling balls are already powerful, and this complication for physics' sake would add a layer of confusion I think...
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STK does not aim to implement realistic physics. This can be discussed I guess, but for STK it should be discussed on the grounds of whether it improves the gameplay, and not on the ground of whether the laws of physics are respected