When we have fun with the robots. Yes. You can have a lot of fun with them.
This is an example of a robot for Sumo Robotics competitions. Specifically for RoboteX challenge. As most of the Sumo competitions have specific requirements for the robot size this one follows the 15cm x 15cm requirements.
Sumo competitions could be quite fun and interesting as the goal is to push the other robot outside of the ring.
Building instructions for the catapult that could be placed over the LEGO Mindstorms EV3 Brick. The idea of the catapult it to throw objects. The fact that it is over the brick makes it very convenient to place the motors below the brick and to use the Catapult.
This robot construction itself was used in the FIRST LEGO League Senior Solutions competition