if I'm not mistaking that domain is affiliated with igggames, they have a bad reputation for modifing game intros with igggames splash screen, adding a drm to the game which acts as a check to see if you removed their modified files or signatures.
Personally not a fan of them, but you can decide yourself.
They say "we bought these games to share, thus we add the watermark."
I've only grabbed two games from the site, the files seemed harmless but quality was lacking. One game consistently black screened across different pcs/OS I had, and the other was missing DLC/expansions that the site claimed to have bundled with the download. I'd double check if any specific communities based around whatever games has anything to say about the site, and acknowledge the possibility of something malicious slipping through if broken/missing files can.