Hunt A Killer: Earth Break – Omega Protocol

From BoardGameGeek:

Five years after the aliens released a deadly virus, those who are immune have taken up shelter in what was once an underground government facility. Welcome to NACS: North American Communications-facility. You are the most recent and last survivor to join NACS and you are contacted by an anonymous resident to investigate strange events. Decode ciphers and solve puzzles to understand the true motivations of your fellow residents. Be the main character in a Sci-Fi adventure! Difficulty: 5/5 - Hard