Good grief. Getting this done took everything I had and more. This is the most infamous room in a knife only run for a reason. Getting through here even with taking damage is bad enough. Knife durability is a major concern and at this stage of the game you realistically can't have more than a few spare knives on hand. I limited myself to three boot knives which is optimistic, but still possible. There is so much potential for unforeseen nonsense that it seems like taking damage is inevitable. It's very easy to get overwhelmed or caught in a bad spot. This took days of practicing and experimenting before I could even have a chance at getting through unscathed. This is my first successful attempt and thank god for that because I nearly lost it right at the end because of the molotov enemy throwing one during a cutscene where I couldn't do anything. Fire damage is somewhat forgiving in this game. Anyway, there simply isn't enough room in the description to give a detailed step by step process of my strategy. There isn't enough room to talk about the myriad of problems you will encounter in this room either. Instead, I'm just going to talk about my theory on the room.
This sequence is divided into two phases, and each phase as two waves of enemies. The first phase is the more difficult of the two by far. It's so bad that if you happen to make it to phase two unscathed, then you have a very real chance of making it through without damage entirely. The ideal way to make it through the waves of enemies in phase 1 is to use the dynamite throwing enemies as effectively as possible. They are likely to kill enemies as long as they are close enough, and it will also bypass the chance of the Plaga Arana from spawning. There are two of those you would have to worry about if you were killing the enemies normally, or letting the brute kill them. When dealing with the enemies, it's best to rely on parries and melee attacks rather than manual stabbing in most cases. The enemies at this point in the game are way too bulky for that, and they don't flinch easily either. It's honestly more practical to hope for critical hits with the melee attacks.
You'll notice that I begin the fight by running around and getting a free knife prompt on one of the enemies. That is an axe throwing enemy, and I want him out of the picture entirely as I don't want to deal with any projectiles. That's why I immediately go after the crossbow enemy right afterwards too. I go after the shield carrying enemy in the second wave for the same reason. Some of you may be wondering why I don't camp on top of the blue container and just knife the enemies as they climb up. This is decent option, but I don't see it as practical compared to either using the dynamite or parrying. It's ultimately more costly on durability, but there is a special component to these blue containers that keeps me away from them. If you spend too much time on top of them, two more enemies will spawn. First is an extra crossbow enemy and later on it's an RPG enemy. It's not hard to react to their spawn and quickly kill them. But doing so has severe consequences which I will touch on in a moment.
There are two brutes. These things are the main reason why knife durability is an issue. As far as my strategy is concerned, killing both of them in the first phase is an absolute must. Leaving either of them alive for the second phase turns that phase into unpredictable chaos. I deemed it an unacceptable outcome. You may think you can use the RPG enemies to kill them, but getting that to work is a crapshoot at best. It also takes multiple rockets to kill them anyway. The reason why I don't allow the aforementioned extra enemies to spawn is because killing even one of them will force the second phase to begin if the only other enemy is one of the brutes. The second brute will always spawn regardless of what phase you are in once the first brute dies. The easiest way to kill the brutes is to have one of the dynamite enemies alive and just use him to blast the brutes to death. I didn't get so lucky this time around, so I had to do it the hard way. The hammer brute is best handled by constantly slashing at his lower legs. You want him to drop to his knees because the knife prompt you get from that is powerful enough to instantly kill him. The one you get from bouncing off of a wall isn't nearly as strong. Unfortunately, this strategy doesn't appear to work with the unarmed brute. I couldn't get him to kneel no matter how much I slashed him. So I turned to using Ashley's wrecking ball to set up knife prompts on him. This is extremely annoying and inconsistent. The key thing to note is the side at which the brute gets wall bounced on. If it's on the right side, then there's nothing to worry about. If it's on the left side, you need to time the knife prompt specifically when the brute is raising its head. Otherwise, you will get hit by the swaying wrecking ball afterwards. (cont. in comment)