KillPhish is an email threat protection add-in designed for Microsoft 365 and Google Workspace environments. The tool scans emails for known threats across multiple platforms including Windows, Mac/iOS, and Android devices, supporting Outlook Desktop, Outlook Web App, and Outlook Mobile applications. The add-in uses artificial intelligence to analyze and assess email safety by examining various indicators including IP addresses, domains, email addresses, keywords, SPF records, and known bad actors. It assigns risk scores to messages to help users identify potential threats. KillPhish includes a reporting button that allows users to flag suspicious emails. When integrated with PhishingBox's Phishing Simulator, it generates Net Reporter Scores to measure individual user risk levels and security awareness within an organization. The tool provides live inbox training by displaying the reasons why messages are flagged as suspicious, helping users learn to identify threats independently. Administrators can customize the messages shown to users after they report suspicious emails. For simulated phishing emails sent through PhishingBox, KillPhish logs reporting actions and updates Net Reporter Scores accordingly. The email scoring feature can be disabled if needed. KillPhish functions as an extension to existing endpoint protection solutions, helping users distinguish between legitimate emails and actual threats across their email infrastructure.