Revert "Collision mur"

This reverts commit 707cf003e833a3597943b4318b3cde9bfda12f6a.
Revert "Revert "Collision mur""

This reverts commit 06d0147c2ffde2251dd97a151f5dee21a7a311fb.
Revert "Revert "Revert "Collision mur"""

This reverts commit 3c427e6c16a1f1cd98c2fb21987ae40802a510a0.