Secret Patrol Missions
From Destiny 1 Wiki
Secret Patrol Missions are a special type of Patrol Missions released in The Taken King expansion (Year 2).
General Information
When you're on Patrol on any destination, there's a chance that you'll just automatically pick a secret mission up. They start off with an objective description that's looks like ????????. Each mission has 3 steps and each step requires a different action, and they've got decent patrol rewards for completing them.
