Video: The robotic versions of competitive sports are usually disappointing at best -- but not when it comes to sumo wrestling. The human titans who try to slowly push each other out of a circular ring are actually far less exciting than these tiny zippy robots whose matches are usually over almost as quickly as they begin. Unlike BattleBots, where the robots are piloted by humans with wireless controllers, these Sumo bots are all completely autonomous. They're also pretty devious when it comes to the tactics and tools they use once a match begins. Mechanical lifts, extending arms and brute force all play important roles in this wrestling league, besides simply just ramming your opponent into submission at high speed as soon as a match begins. Nothing gets destroyed by the match's end, which is admittedly a little disappointing, but you'll still find yourself cheering for a favourite.