Blue Keycard

The Blue Keycard is an essential item in Rust, allowing players to unlock numerous advanced monument puzzles. This keycard is a step above the basic green keycard, and it's pivotal for accessing high-tier loot areas. You can acquire a Blue Keycard through fishing and gutting high-tier fish or by successfully navigating the green monument puzzles found at the Harbors, Satellite Dish, or Sewer Branch.

Several critical monuments require the Blue Keycard to complete complex puzzles. These locations include the Airfield, Arctic Research Base, Military Tunnels, Missile Silo, Oil Rig, Power Plant, Trainyard, and the Water Treatment plant. To enhance your gameplay and reap valuable rewards, knowing where to use the Blue Keycard is imperative.

It's worth noting that the Large Oil Rig doesn't hinge on the Blue Keycard to access its Locked Crate. However, it's advantageous as it grants entry to four military crates, which can significantly boost your resources and armaments.

As a player, remember that these keycards have limited uses and can eventually expire, so planning your expeditions and managing your keycards effectively is vital. Always be prepared to encounter resistance; other players are also contending for the precious assets protected by these puzzles.