Resident Evil 4 - Keycard Access Terminal Puzzle Guide
Override the access levels of your Lab Keycard in Resident Evil 4.
The third zone in Resident Evil 4 is the Island. Once again, Ashley has been kidnapped, and Leon has to free her. But, before you can do that, you'll need a Level 3 Keycard. Here's our Resident Evil 4 Keycard Access Terminal Puzzles guide to help you with this particular objective.
Resident Evil 4 Keycard Access Terminal Puzzles guide
The Resident Evil 4 Keycard Access Terminal Puzzles guide takes place in the laboratory area of Chapter 13. Continue through the level until you reach the Merchant hub in the kitchen, which is connected to the lab hallway.
![Lab area map.](https://www.gamespot.com/a/uploads/original/1816/18167535/4116143-residentevil4keycardaccessterminalpuzzlesguidelevel3keycard-1a.jpg)
Puzzle #1: Dissection Room - Level 1 Keycard
- Go to the Power Control Lever and flip the switch. You may also unlock the nearby shutter gate so you can return to the Merchant's hub a lot faster.
- Head to the Dissection Room, where you'll see a terminal. You'll notice several symbols, subdivided into sections. The goal here is to press the buttons so that each set of symbols will be rotated, forming an unbroken line from the "Power" source at the top-left, circulating to the two nodes with electricity icons.
- For the first Resident Evil 4 Keycard Access Terminal Puzzle, we simply pressed the first two buttons (we ignored the third). After a bit of trial and error, you should have the same diagram seen in the image below. Press the fourth button to unlock the door.
![The solution to the first puzzle.](https://www.gamespot.com/a/uploads/original/1816/18167535/4116144-residentevil4keycardaccessterminalpuzzlesguidelevel3keycard-1b.jpg)
You can then pick up the Level 1 Keycard that's on a table in the Dissection Room. However, when you attempt to exit this area, a Regenerador will spawn. These enemies are unnerving, as they're nigh unkillable since they'll flop around and regenerate their body parts. At best, you could shoot your foe in the head to stun it for a couple of seconds, but you should definitely run away or parry its attacks.
![Don't bother wasting your ammo on Regeneradors.](https://www.gamespot.com/a/uploads/original/1816/18167535/4116145-residentevil4keycardaccessterminalpuzzlesguidelevel3keycard-1c.jpg)
Puzzle #2: Freezer - Level 2 Keycard and LE5 submachinegun
- Run past the Regenerador and return to the Power Control Lever so you can flip the switch again.
- Next, head to the Freezer, which can now be opened by your Level 1 Keycard.
- Inside, there's another console. The same concepts still apply when it comes this Resident Evil 4 Keycard Access Terminal Puzzle: press buttons to form an unbroken line. The difference here is that five electricity nodes need to be powered up.
- In our case, we simply fiddled around with the first three buttons. Again, a bit of trial and error is in order. You should then have something akin to the image below. Press the fifth button and you'll get this part done.
- You should then enter a small room that has the LE5 submachine gun.
![The solution to the second puzzle.](https://www.gamespot.com/a/uploads/original/1816/18167535/4116146-residentevil4keycardaccessterminalpuzzlesguidelevel3keycard-2a.jpg)
Anyway, with power successfully rerouted, you can interact with the terminal at the back wall of the Freezer. This will override your Keycard's access level. But, this is going to take a while, roughly a minute or so.
During this time, another Regenerador will crawl out of a body bag. Stun and parry, but don't bother wasting all your ammo trying to kill it. You'll hear a programmed voice saying that the process is done, so grab the Keycard and make your way out of there.
![Another Regenerador will appear while you're waiting for the override process to be completed. Don't waste your LE5's bullets on it.](https://www.gamespot.com/a/uploads/original/1816/18167535/4116147-residentevil4keycardaccessterminalpuzzlesguidelevel3keycard-2b.jpg)
Incubation Room - Level 3 Keycard and Biosensor Scope
You should now be able to enter the passage that leads to the Incubation Room. This is the large metal doorway at the end of the hall that's close to the Merchant's hub. When you reach the bottom floor, you'll see four Regeneradors frozen in stasis tanks. Here's what you need to do:
- Don't destroy any of the tanks or shoot the Regeneradors yet. Instead, go to the control room at the back and pick up the Biosensor Scope. This can be attached to any compatible weapon (i.e., rifles). When you zoom in, you'll see the parasites inside the bodies of Regeneradors (at least three). The idea now is to destroy each parasite with precision shots, which will kill these creepy creatures more efficiently.
- If you want to complete the "Two Bugs, One Stone" achievement, find a Regenerador that has two parasites that are close to each other. Line up your shot so that one bullet is able to kill both parasites.
- As for the main objective, you'll have to kill the Regenerador that has a wrench stuck inside its body. Pick up the wrench and use it on the terminal in the control room. This will let you place the Keycard inside.
- Once again, you'll have to wait for the process to be completed, and half a dozen enemies will rush your position while this is going on. After eliminating all of them, you can grab the Keycard.
![Attach your Biosensor Scope to a compatible weapon and kill the Regenerador that has a wrench inside its body. Then, use that wrench to fix the nearby terminal for your Level 3 Keycard. Just watch out for the enemy mobs that will show up when the overriding process begins.](https://www.gamespot.com/a/uploads/original/1816/18167535/4116148-residentevil4keycardaccessterminalpuzzlesguidelevel3keycard-3a.jpg)
This will complete the Resident Evil 4 Keycard Access Terminal Puzzles, as well as other related objectives. All that's left is to make your way back to the Holding Cell where Ashley is, which will conclude this chapter.
Resident Evil 4 has more mechanics and secrets for you to discover. You can learn more in our guides hub.
Got a news tip or want to contact us directly? Email news@gamespot.com
Join the conversation