Create a mud slide on Monte Diabolo (in Costa Rica)! Run the simulation and select the Mud-Particle (the black square) in the Gallery. Use the Draw Rectangle tool to drop a bunch of mud particles on the mountain and let it settle down. Clicking on the + with the Hand tool will increase the friction of the Mud-Particles, whereas clicking on the - will decrease it. The + and - are hard to see, but they are somewhere in the clouds. Observe the effects of the variation in friction. When using this within AgentSheets, add a Sonifier in your worksheet to hear the sound of the mud slide. More Information