Constella Hunter is a deep OSINT investigation platform designed for cyber threat investigations and threat actor attribution. The tool aggregates data from Surface, Deep, and Dark Web sources, as well as social media platforms, to help investigators connect anonymous identities to real-world actors. The platform provides access to the Constella Data Lake containing over 124 billion compromised identity records from data breaches. Investigators can search across more than 30 different attributes and keywords to identify connections between threat actors, their tactics, techniques, and procedures. Hunter includes visualization capabilities through a graph workspace that allows analysts to map relationships between entities and attributes. The platform supports bulk searches, search history tracking, and domain exposure investigations. The tool incorporates machine learning-generated malicious scores to provide context on entities associated with malicious breaches. Password pivoting functionality enables investigators to identify additional accounts using passwords collected from breaches. Hunter employs proprietary encryption methods to protect search queries from external detection. The platform offers configuration options for proxy usage to obfuscate investigations and includes audit capabilities to monitor search activities conducted within the system.