Earlier this year, [redacted] encountered a relatively new ransomware threat actor that called themselves BianLian. We observed the actor deploying custom malware that was written in the Go programming language, which posed some initial, but not insurmountable, reverse-engineering challenges. BianLian used subtle techniques to exploit, enumerate, and move laterally in victim networks to remain undetected and aggressively worked to counter Endpoint Detection & Response (EDR) protections during the encryption phase of their operations.