An Access Card is a single-use item that can unlock an Access Card Panel of the same color. This will usually cause a door to unlock, but it may also trigger other events instead, such as deactivating a force field, exposing a switch, or triggering an explosion.
Access Cards are one of three colors:
Only one Access Card of a given color may be carried at once.
If a level contains multiple Access Card Panels of the same color, then the Access Card Panels may be coupled or uncoupled. Coupled Access Card Panels will automatically unlock when an Access Card is provided to any of the coupled panels. Uncoupled Access Card Panels only appear on custom user maps and require a unique Access Card for each panel
- The color of the Access Card depends on its palette color. It is therefore possible for some user maps to implement additional Access Cards, such as green, white and black.
- In Duke Nukem: Manhattan Project, Duke comments that he hates looking for Access Cards.
The Access Card in other games
- In Duke Caribbean: Life's a Beach, the Access Card is renamed the Credit Card.
- In Duke Nukem: Manhattan Project, there is one Access Card to find per level (along with one trapped babe). This Card must be found and used on the force field-protected door to continue.