What does it mean to dream of raining on stones?

I dreamed that it rained on stones, and I rushed into a garden-shaped building with two friends in time to sell hot drinks. Someone in the back drove a car and tried to enter as if fleeing in the rain. But there was something like a robot that stopped them. They had to force them, but one of them was killed by a knife on the calf, so they had to cut off the calf in order to save their lives. The other heart was cut apart. They shed a lot of blood. The staff can't stop the robot even if they scold the robot. The staff kindly hugged the injured person lying on the ground as a dying comfort. I was very scared in my dreams. Two friends, they were a couple, talking and laughing. Said that if their car would be able to withstand this stone rain.

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