Online shooter Dark And Darker has been caught in a firestorm of controversy after it was removed from Steam due to a DMCA claim from Korean gaming giant Nexon. Now, it seems that the dispute has escalated to a lawsuit, with Nexon suing developer Ironmace in the Western District of Washington over alleged copyright infringement.

The nut of the dispute seems to be that Ironmace is comprised in part by former Nexon staffers who left to form their own studio. Nexon claims that those staffers have used "materials and assets" from a project that they worked on during their time at the large company, known as P3, in creating Dark And Darker. Ironmace has reportedly been subject to a police raid due to the ongoing clash, and even told fans to torrent its game client in order to participate in its fifth playtest in April.

As spotted by Eurogamer, the lawsuit claims that two specific employees of Ironmace signed one year non-compete clauses as part of their agreement with the company, which would prevent them from "working in the same line of business that could potentially infringe on Nexon's trade secrets." The suit also includes side-by-side image comparisons from P3 and Dark And Darker in order to prove similarities between the two, citing details such as a potion worn on the character's hip.