In case you don't understand what "mad button mashing" is it is where you hit the attack buttons or freak out on the controls in a game in a panic to try to defeat something that is in the process of killing you.
This might work in some games or perhaps even most games back when we were using controllers with 2 buttons on them, but this is NOT going to work in Hollow Knight, especially in boss fights.
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You learn this pretty early on in the first boss fights of the game and the same notion carries on throughout the remainder of the game. You simply cannot just wail away on enemies in the game and expect to not get worked. This is because touching virtually any enemy in this game is going to result in you taking damage just like a lot of game out there. It sometimes seems a bit silly to me that this is the case, that by just touching something you would get hurt, but that is the way this game is all the way through.
Try to rage your way into hurting an enemy and you are not going to get very far.
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I found this most evident on my first playthrough during the encounter with the Mantis Lords. Your opportunity to hit them is very small except during one phase of their attacks but even then you need to be very careful because there are things flying at you (which of course will Van Damage you and the spike pits on both sides of the arena will do the same.
For the most part I have found that a good strategy with most of the bosses in the game is to at first don't even focus on attempting to strike them but instead to take 20 seconds or so to try to understand their attack patterns before even attempting to dish out any attacks of your own.
This is crucial to winning any boss fights in this game and all the times that I have not used this strategy I have inevitably failed.
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I wouldn't say that there are a tremendous amount of bosses that are full of shit, but in the regular course of the game as you make your way to the first and easiest ending these guys are probably the most cumbersome. I say this because they have 3 attacks, two of which are not telegraphed at all and unless you are a god at this game you are going to be fighting two of them at the same time.... and there are 5 of them. 6 of them if you don't know about dropping the chandelier on one of them pre-fight.
I probably fought these guys something like 30 times before I got past them and unlike many of the other bosses in the game, this fight is not optional.
In the end most of the bosses have a method of trapping you in the corner and bouncing around on your head until you are dead. In those instances it is really important just to get the hell out of there and not even worry about trying to get a strike in. You will NEVER win this tit for tat exchange.
Money Spider is one of those YT'ers that makes me feel as though I absolutely suck at every game that I play and when you watch him play he makes it seem like these fights are easy. He is on a totally different level as far as gaming is concerned. I can assure you that this fight with the Failed Champion is really difficult.
I am not anywhere near his level of ability and I don't think most mortals are or ever will be.