Hedgehog

The Hedgehog is an obstacle that first appeared in Ninja Warrior of Roblox 6. This obstacle has many thin blocks attached to a part on a motor that competitors must try to pass, without getting knocked off. The obstacle was relativity glitchy, and would sometimes fling people off the obstacle, or even stop for a few seconds. It didn't eliminate many competitors, and the obstacle was replaced by the Swing Jump in Ninja Warrior of Roblox 7.