The lawsuit against them is regarding allegedly using 'trade secrets' and proprietary assets from Nexon, where a number of the team members previously worked. After Nexon killed Project P3 the IRONMACE devs left the company and started their own game based on the premise of an extraction dungeon crawler. After seeing their early success in alpha, Nexon got jealous and sad so the submit a frivolous lawsuit with a cease and desist / DMCA takedown on DaD on Steam.

When claiming stolen assets in their initial filing, Nexon cited publicly purchased engine store assets which is obviously ridiculous.

Both IRONMACE and Nexon are based in Korea so they are still in their legal battle there and as such DaD isn't currently released in Korea. I guess the US case is either dismissed or at least the cease and desist was lifted.

Long story short, nothing to do with Bethesda or elder scrolls assets. IRONMACE made an awesome game and their old employer is sad they can't cash in on something they didn't contribute to at all. All my homies hate Nexon.