The Secret Triwizard Challenge

You use Aguamenti to spray the ground in front of the spider, then turn to run.
The spider is running too fast for the mud to stop it and skids out of control. It tumbles right into you, pinning you to the hedges of the maze, and though the spider is on its back and can't eat you, you can't move either. You try to get free, but you're stuck pretty well. The spider can't get off its back to move either. You sigh.
After a few minutes of not being able to do anything, the monitors on brooms come and rescue you from your situation and take you out of the maze. This sucks. YOU LOSE!
End Of Story