Audio makers sell methods of sneaking songs on to Roblox to one another like furtive weapons dealers; some can go for thousands of Robux, or roughly $20-40 (€16-32).

Video-game company Roblox said Friday that Mattel is providing licenses for Polly Pocket, Street Sharks, Rock 'Em Sock 'Em Robots and Matchbox. The licenses would soon be available for creators to ...