Checkpoints can open up new and unique routes to reach the objective. However, it takes more than just standing on a point to open these doors. Every player starts the round with a Keycard which can be used to open or close checkpoints your team owns. Skilled mercs can even steal enemy cards with a swift hand and some well placed bullets. Watch your back, though; all Keycards carried are dropped on death, so survival is a must!
Lost keycards will automatically return to their owner after 30 seconds.

You can manually drop an enemy keycard, but it will disappear and immediately return to whoever lost it.

Enemy keycards cannot be brought into team-only areas, such as spawn rooms.