Wheels are part of the pipe that release liquids. To turn on the wheel you press and hold the wheel. When you let go then the wheel stops and whatever was coming out will stop. Different colors release different liquids, as stated below:
Purple: Poison Water
Green: Toxic Ooze
Light Brown: Mud (Driest form)
Dark Brown: Mud (Wettish form)
Gray: Different liquids in different circumstances, if ooze is in a drain (entrance to a pipe), and is linked to a gray wheel, ooze will come out.
- When a mud converter is connected to a wheel, it releases mud in its wettest form.
- When a wheel (not gray) is present then there will be no drain.
- Wheels that are attached to a pipe with a drain will be gray. It works when a fluid touches the entrance, and it will not go through unless you touch the wheel.