A team of modders working to make the unreleased Halo Online playable have halted work after Microsoft contacted them in an effort to protect its intellectual property.

Halo Online is a free-to-play version of the popular shooter series that was only ever offered in a closed beta test in Russia in 2015. After years on ice, a mod that makes it playable the world over is getting a brand new version on April 20.

When you first heard the words "free to play" and "Halo 3 engine", you might have dismissed that weird Russia-only Halo shooter for the PC. You might also have been a little too hasty.

It didn't take long for modders to start figuring out a way to get the Russia-only closed beta of Halo Online working elsewhere. In fact, excellent progress was being made to this end until Microsoft caught wind of it and rather hastily killed the project with a DMCA notice.