This blog post explains what "NTL rar" likely refers to—usually the or scripts for the Diablo 2 D2NT mod —and provides guidance on how to download and manage these files. Understanding and Downloading "NTL rar" Files
The official repository is at libntl.org , where you can find the latest Unix ( .tar.gz ) and Windows ( .zip ) distributions.
The .ntl file suffix is often related to scripts for the D2NT mod in Diablo 2. Where to Download
