It looks like you’re referring to a (a text file containing leaked usernames and passwords, often used for unauthorized account access) [1].
If you are concerned about your own account security, here are the best steps to take: immediately to something unique [4]. 18K LOL USERPASS.txt
via the Riot Games website to add an extra layer of protection [5]. It looks like you’re referring to a (a
to see if your email address has been involved in any known data breaches [6]. 18K LOL USERPASS.txt