It looks like Lego is creating a 'Minecraft' competitor called 'Lego Worlds'

Lego may be working on a "Minecraft" competitor called "Lego Worlds," according to an advertisement discovered by a member of Lego fan site Eurobricks.

The advertisement in question was found on the back of a Lego instruction booklet for Lego set 60097, "City Square," and features some artwork accompanied by the tagline "Explore. Discover. Create."

There's also a link to a website - Lego.com/Worlds - but that link brings up Lego's 404 page, so it appears the advertisement might have run before Lego had time to set the website live.

The artwork for Lego Worlds certainly looks like it could be from a "Minecraft"-style video game, and the tagline does sound similar the tagline for "Minecraft," which is "Build. Play. Explore."

Creating a "Minecraft" competitor would also make a lot of sense for Lego: "Minecraft" is often described as a sort of virtual Lego sandbox where you can build whatever you want and then explore your creation or the creations of others. The popular video game has more than 100 million registered users and has sold more than 60 million copies across PC, Mac, Xbox, PlayStation, Android, and iOS.

Lego and Minecraft have partnered in the past, with Lego creating physical box sets with "Minecraft" branding, but it looks like Lego may be ready to create a sandbox-style video game of its own.

After its smash success following its launch in 2009, "Minecraft" has become one of the best-selling video games of all time. In September 2014, Microsoft acquired Mojang, the studio behind "Minecraft," for $2.5 billion.