Are you using a or a third-party modification ?
The EMP.dll file is a dynamic link library (DLL) — a collection of small programs that can be used by larger applications when needed. In the context of Watch Dogs: Legion , this specific DLL is not an official game file. It is almost exclusively associated with cracks, most notably those created by the infamous cracking group (hence the "EMP" in the filename). If you have a legitimate copy of the game from official platforms like Steam, Ubisoft Connect, or the Epic Games Store, you will never encounter an EMP.dll error or need to download this file.
Before attempting to download a replacement file, please be aware that downloading DLL files from unknown third-party websites can be dangerous, potentially exposing your system to malware.
Malicious actors are well aware that people search for emp.dll . They upload infected files disguised as the crack. A virus on your computer can achieve many things: steal passwords, compromise credit card details, install ransomware, or use your machine for Bitcoin mining. As one user reported on the Malwarebytes forum, after using an Empress crack, their antivirus flagged EMP.dll as a Trojan, leading to fears of compromised passwords and financial data. While they believed it was a false positive, the anxiety and risk are very real.