Keycards are dropped when a Boss enemy is eliminated. The player can then pick up the keycard like any other item, taking up 1 inventory slot. When held, the keycard will show a three dimensional arrow on the screen which points towards the vault that it unlocks. The keycard will also produce a sonar sound alongside it.
There is an unused Shadow/A.L.T.E.R. keycard inside the game's files.
The Agency Keycard • The Grotto Keycard • The Yacht Keycard • The Shark Keycard • The Rig Keycard • The Fortilla Keycard • The Authority Keycard • Catty Corner Keycard • Doom's Domain Keycard • Stark Industries Keycard