The “How to Train Your Dragon” game on Roblox has more than 28 million visits. Over the weekend, the movie raked in $83.7 million in ticket sales in the U.S. and Canada, surpassing expectations.

Technically an “experience” within the game-creation platform Roblox, it smashed its own record for concurrent users by reeling in 16.4 million active players on Saturday. It is a genuinely ...