In the game's epic finale, Joel learns some startling news: the Fireflies can extract Ellie's infection to create a cure for humanity. The only catch is that it will cost her life. After building such a strong bond with her over the game's story, Joel isn't about to walk out of the hospital without putting up a fight. While Joel will be sacrificing a chance to save humanity, he'll be saving the one thing that matters more to him than anything else.
The final two chapters of The Last of Us Part 1 provide the emotional and satisfying conclusion to the game's stellar narrative, while also providing enough engaging combat to keep players on their toes. The first of the two chapters, "The Firefly Lab", consists of Joel's fight against the Fireflies in the game's climax. While short, the epilogue chapter "Jackson" still holds a secret or two as it leads up to the iconic and much-debated ending of The Last of Us Part 1.
The Firefly Lab: The Hospital
The Firefly Lab chapter will consist almost entirely of combat. This will begin immediately after the cutscene where to Firefly soldiers search the hallway. Climb through the nearby window and wait for the two soldiers to walk down the hallway.
After they investigate the body of the soldier Joel killed in the cutscene, they’ll split up to look for Joel. Either one soldier will search Joel's room, or they'll split off and search around nearby. Either way, once they're split up, kill each of them silently.
Go back and hide. Another soldier will come over and find the bodies. Wait for him to walk by to kill him.
He’ll drop the last weapon to collect in the game: the assault rifle.
Another soldier will come by searching for the bodies; kill him. Leave the room and go down the hallway. Hide behind cover as more men will come searching.
Two men will stand guard at the far-left corner of the room will two others will search down the right side of the room. First take out the two men searching. As they approach Joel, throw a brick or bottle behind them.
When they have their backs to Joel, sneak up on the one closest and silently kill him. Then sneak up and silently kill his partner.
Go and hide behind the corner of the small room on the left. Two soldiers will be guarding the exit up ahead. Throw a nail bomb in their general direction to kill both at the same time.
Once they're dead, go to the exit in the far-right corner, with the "West Wing" sign hanging above.
In the hallway, hide behind the hospital bed in the middle of the hallway. Three soldiers will run by; wait for them to pass, then continue forward.
In the next room, a soldier will burst through the doors ahead. Run up and attack him, then press the triangle button to go through the doors and into the stairway.
Walk up the stairs and press the triangle button to open the door. There won't be much combat for a little while, so use this time to stock up on supplies and craft any necessary tools. There will also be several collectibles here. On the desk in front of Joel will be an artifact.
To the left of the stairway will be a small room with another artifact inside.
The door behind the reception desk can be unlocked with a shiv. Inside will be supplies and a firefly pendant.
Exit the room. In the next room, search through the tents for supplies and another artifact.
Then, go up to the window at the far end of the room, where Joel will see soldiers preparing in the next room.
In the next hallway, soldiers will be guarded. Throw a smoke bomb in front of the doorway and sneak past.
Just to the right of the hallway is an open door. This will lead to a bunch of small side rooms where it’ll be easier to find cover, whether for stealth or combat. This is the final combat encounter in the game, so don’t be afraid to go all-out if necessary.
When everyone is killed, go to the main hallway and walk through the door labeled “Pediatrics”.
In the next hallway, go through the door on the right. Inside will be an artifact.
Go back into the hallway and walk down through the red door. This will lead to the operation room, where doctors are operating on Ellie.
Go into the room. One of the doctors will try to stop Joel. Kill him.
Go up to Ellie and press the triangle button to pick her up. While this is the emotional climax to the whole game, it can also be little confusing as to where to actually go from here. After leaving the operating room, immediately turn around and turn into the room on the right.
After running down a linear path for a little while, Joel will come to a dead end with two Firefly soldiers looking for him. Go through the locker room on the right.
At this point, run straight into the open elevator at the end to conclude the Firefly Lab chapter.
Jackson: Epilogue
After the cutscene, there's a short epilogue where players will briefly play as Ellie as she and Joel return to Jackson after their long journey. As players gain control of Ellie, Joel will lift the fence just ahead. Go up and press the X button to go through the fence.
Follow Joel for a little bit, then turn right. At the edge of the cliff on the right will be an abandoned truck with a comic inside.
Continue following Joel through the forest. Eventually, Joel will climb up a small ledge, lending down a hand to lift Ellie up. Press the X button to grab onto Joel's hand, triggering the final cutscene and concluding the game.
The Last of Us Part 1 is available on PlayStation 5 and PC.