Rotating Knife Blades
The Rotating Knife Blades are a trap in Lara Croft: Relic Run.
These blades generally are found in one of the outer lanes. They however can be extended into the middle lane. When they come as a set your only way past is to either slide underneath, or to jump over them. When there is only one of these in an area with three clear lanes, you can sidestep them by switching into the far lane.