Roboto-Ball was a popular Arkeyan sport in Skylands that was mostly played in the Lost City of Arkus. It was once popular among Arkeyans; their favorite part was that the roboto-balls themselves had the tendency to explode. It made for some exciting action on the field, but it also led to many accidental explosions when these roboto-balls were used at home, which in turn led to property damage and the occasional reveal of hidden treasure stashes.
Roboto-Balls are used as items in Skylanders: Giants. The player can make Roboto-Balls appear in Lost City of Arkus and Bringing Order to Kaos! by activating specific button pedestals. The balls have similar properties to Mega Bombs: they must be manually rolled to their destination by the Skylander, and they are used to destroy large structures such as walls. Any enemy that comes in contact with a rolling Roboto-Ball is instantly defeated (unless the enemy has shields up or unless Armor is triggered).
Bouncer is the most well-known Roboto-Ball player.
Weapon Master says the sport got discontinued in the Lost City of Arkus, although he then says that the Skylander is permitted to 'play with it'.