Mastering the Rat King Boss Fight in The Last of Us Part II Remastered

Facing the Rat King: A No Damage Perspective

There are moments in The Last of Us Part II that test everything you have learned. The Rat King encounter, deep in the hospital basement, is one of those moments. On Grounded+ difficulty, with a no damage run on the line, this fight forces you to respect every mechanic the game has taught you. I have spent hours replaying this section, studying its patterns, and learning how to survive without taking a single hit. The Rat King boss fight is not just a test of reflexes. It is a test of patience, resource management, and environmental awareness.

The setting itself tells a story. The hospital basement is a cramped space filled with overturned gurneys, bloodstained tiles, and the distant hum of emergency lights. The air feels heavy. The Clicker sounds echo off the walls, and you know something massive is waiting. When the Rat King finally emerges from the darkness, it is a grotesque fusion of infected bodies, a writhing mass of Shamblers and Bloaters fused together by the Cordyceps infection. The design is horrifying in a way that feels earned, not gratuitous. Every time I enter this room, I feel the same tension I felt on my first playthrough.

Understanding the Rat King's Anatomy

The Rat King is not a single enemy. It is a collection of infected entities bound together, and each part behaves differently. The core is protected by layers of Shamblers that act as armor. Bloaters sit within the mass, ready to spew toxic spores that obscure vision and deal damage over time. The key to a no damage run is recognizing which part to attack and when. You cannot just unload ammunition into the center and hope for the best. You need to peel away the outer layers methodically.

I learned this the hard way during my first attempt on Grounded+ difficulty. I tried to brute force the encounter with the Mounted machine gun mounted on a nearby table. That strategy ended quickly. The Mounted machine gun makes you stationary, and the Rat King summons smaller infected that swarm your position while the Bloaters launch spore clouds. You become overwhelmed in seconds. The better approach is to use the environment to create distance. The pillars and overturned beds provide cover, but they also limit your mobility. You have to move constantly, never staying in one spot for more than a few seconds.

Preparing for the Fight

Before you even enter the hospital basement, your loadout matters. On a no damage run with maximum upgrades, you have access to every tool, but that does not mean you should use them all. I found that a silenced pistol, a hunting rifle, and a few smoke bombs are more effective than carrying heavy explosives. The Rat King boss fight requires precision, not power. Each shot needs to count because reloading leaves you vulnerable. I also recommend having at least one health kit equipped, even though you plan to avoid damage. The game sometimes throws unpredictable attacks, and having a backup can save your run.

The chronological mode in The Last of Us Part II Remastered changes how you experience the story, but the gameplay mechanics remain the same. If you are playing through the game in chronological order, you will face the Rat King after experiencing key moments with Ellie and Abby. This context adds emotional weight to the fight. The Rat King is a physical manifestation of the infection that has torn apart so many lives. It is not just a monster. It is a reminder of what the Cordyceps does to people.

The Fight Itself: Phase by Phase

The Rat King boss fight has three distinct phases, and each one requires a different strategy. In the first phase, the Rat King moves slowly, using its bulk to block doorways and corner you. The Shamblers on its surface will detach and attack independently. Your goal is to eliminate these detached Shamblers while avoiding the Bloaters' spore clouds. I found that using the hunting rifle from a distance works well here. One shot to the head of a detached Shambler takes it down, and you can retreat behind cover while the Rat King advances.

In the second phase, the Rat King becomes more aggressive. It starts charging across the room, and the Bloaters inside it begin launching spore clouds more frequently. This is where the environment becomes your best friend. The meat locker in the corner of the basement offers a narrow corridor where the Rat King cannot fit. You can lure it toward the entrance, then duck inside and take shots at its exposed weak points. But be careful. The meat locker also contains hanging hooks that can block your movement. I have died more times by getting stuck on those hooks than by the Rat King itself.

The third phase is the most intense. The Rat King's outer armor is mostly gone, revealing a pulsating core. This core is vulnerable, but the Rat King also spawns a constant stream of smaller infected. You have to split your attention between the core and the adds. The Mounted machine gun can be useful here if you have cleared the area of smaller threats first. I recommend using it only when the Rat King is stunned from a well-placed explosive. Even then, you should fire in short bursts to maintain accuracy. The recoil on the Mounted machine gun can throw your aim off, and every wasted bullet is a risk.

All Collectibles and Maximum Upgrades

One of the goals of a 4K ultra gameplay walkthrough is to collect every artifact and note scattered through the world. The hospital basement contains several collectibles, including a note from a doctor describing the early stages of the outbreak and a Firefly pendant that belonged to one of the WLF soldiers who died here. These items add depth to the world, but they also put you at risk. To grab them without taking damage, you need to clear the room first. I found that using smoke bombs to distract the Rat King while I sprinted to collectibles was the safest method. The smoke does not last long, so you need to know exactly where each item is before you start.

Maximum upgrades change the dynamics of the fight significantly. A fully upgraded pistol has less recoil and faster reload, which lets you maintain pressure on the Rat King's weak points. The hunting rifle with a scope upgrade gives you cleaner shots from across the room. But upgrades also create a false sense of security. I have seen players rely too heavily on their upgraded weapons and forget the fundamentals of movement and positioning. The Rat King boss fight punishes overconfidence more than anything else.

Lessons from the Meat Locker

The meat locker is a small, bloody room that serves as both a refuge and a trap. During my no damage run, I spent a lot of time in that meat locker, learning its corners and the timing of the Rat King's charges. The mounted machine gun sits just outside, and the temptation to grab it is strong. But every time I picked it up, I found myself pinned down by spore clouds. The smarter play is to use the meat locker as a reset point. When the Rat King gets too close, you retreat inside, let it pass, then pop out and take shots at its back. This tactic requires patience, but it works.

The Scar construct that forms the Rat King is a reminder of how the infection spreads and mutates. In The Last of Us Part II, the infected are not just obstacles. They are the result of a broken world. Ellie and Abby both carry their own scars, and facing the Rat King feels like facing the infection itself. The fight is not just about survival. It is about confronting the horror that has shaped everyone's lives.

Final Thoughts on Grounded+ No Damage

Completing the Rat King boss fight on Grounded+ difficulty without taking damage is one of the most satisfying achievements in the game. It requires you to master every system: movement, aiming, resource management, and environmental awareness. The 4K ultra gameplay of The Last of Us Part II Remastered makes every detail visible, from the veins pulsing in the Rat King's core to the dust motes floating in the hospital basement light. That clarity helps you read the enemy's movements and react faster.

If you are attempting an all collectibles run in chronological mode, the Rat King boss fight is a major milestone. Once you clear it, the rest of the hospital feels manageable. The experience teaches you to stay calm under pressure, to use every tool wisely, and to never underestimate an enemy just because you have faced it before. The Rat King boss fight is a masterclass in encounter design, and beating it without taking damage is a testament to how well you understand the game. Every time I walk out of that basement, I feel like I have earned my place in this brutal world.