Peter Molyneux's experimental chiseling game Curiosity has unearthed the creative side in many gamers, with many amateur works of art being carved into its massive cube only to be destroyed as others seek to progress to its mysterious core.

The most popular carving? Need you really ask?

“Far and away, the most number of single pictures have been penises,” Molyneux told the crowd at this year’s Montreal International Game Summit via Skype.

However, as they would with an unwanted tattoo or offensive graffiti, many players have taken to redecorating the pictures, transforming them into less salacious images.

Other images appearing in the cube include an exceptionally detailed picture of a woman holding an umbrella, a Space Invader, and the Pokemon Mew.

The game has been so unexpectedly popular that its servers have been overwhelmed, putting the team into a crunch mode and torpedoing Molyneux's plans to appear at the Montreal show in person.

“My assumption was that a few thousand people would start tapping away at the cube,” said Molyneux said, adding that perhaps a few thousand would be added each day.

Instead, the game hit 50,000 players within three hours of launch, and its userbase has grown to almost 2 million players.

Later in his keynote, Molyneux implored indie developers to take advantage of new platforms to realise the potential of the gaming medium.

“Back in the '80s, the dream that we all had in this industry was that we would be truly another form of entertainment,” he said.

“You know what? To a certain extent we failed on that dream. We failed in it because we've made some fantastic experiences for a very small number of people. Now is the opportunity to make fantastic, amazing, unique experiences, to use all this technology to make amazing, delightful, incredible worlds for millions of people.”