Time for action – how to "handle" Nurse Slipperfoot
You can mess around with each node's Bezier handles by clicking on the dots in the Animation window, selecting a handle style from the right-click menu, and pulling the little gray handles around, provided the keyframes are set to Flat, Broken, or Free Smooth. To correct this animation simply, we're going to apply a boring straight line between all of the key points.
In the Animation window, press Ctrl/command + A to select all of the nodes in the animation.
Right-click/alternate-click on any one of the nodes.
Navigate to Both Tangents | Linear to flatten the curves between the nodes.
Test your game.
That's better! Nurse Slipperfoot's still not facing the right direction as she runs, but at least she's no longer in need of an exorcism.
Note
Note: If Nurse Slipperfoot is still phasing through walls, you may need to revisit your keyframes and make sure she's positioned correctly at each corner of the hallway on frames 0 (bottom-right), 120 (top...