Sqword is a word game where you try to make as many words as you can in a five-by-five square grid, earning more points for longer words. It was made by Josh C. Simmons and his friends, and is freely available at sqword.com. However, it’s also been picked up by multiple browser game portals, who took it without permission and ran it behind their own ads for profit.

As reported by 404, Simmons found out Sqword was being monetized by sites that were simply embedding it with iFrame, and decided to do something about it. “The mature and responsible thing to do would have been to add a content security policy to the page”, he wrote. “I am not mature so instead what I decided to do was render the early 2000s internet shock image Goatse with a nice message superimposed over it in place of the app if Sqword detects that it is in an iFrame.”

On the off-chance you have somehow missed out on encountering Goatse over the years, it’s a photograph of a bent-over man stretching out his anus that’s been used to shock and troll internet users since it was uploaded to the domain Goatse.cx in 1999. Simmons added the text, “I steal other people’s code because I’m a total hack” to the version displayed on sites that stole his game.

“It has been one of my greatest achievements as a dev”, he went on, “to live-deploy a massive goatse image to at least 8 domains that aren’t mine.” Simmons finished with a warning. “Let this be a lesson to you—if you are using an iFrame to display a site that isn’t yours, even for legitimate purposes, you have no control over that content—it can change at any time. One day instead of looking into an iFrame, you might be looking at an entirely different kind of portal.”