One of the main things that I like about Hollow Knight is the fact that they built in 3 endings and I only know this because of the fact that I have read about it online. I have not achieved all of them because the 2nd one involves defeating the dream bosses and the 3rd is a special ending that is reserved for only the sort of hardcore players with a level of patience and determination that I do not possess.
These are the kind of players that are happy playing Super Meat Boy or I Wanna Be The Guy. These types of games can normally only be defeated with some sort of internet assistance and while I am sure some people out there are and have been capable of defeating Hollow Knight's 3 possible endings I would imagine that a vast majority of people have used some amount of internet help in order to get the job done.
The last two are too difficult for me and while I DO think that I COULD accomplish them if I really tried. I do not enjoy fighting the same boss over and over and over again. Normally, in one sitting 10 times is the most you are going to get out of me before I walk away, perhaps waiting quite some time before I actually give it another shot.
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The dream bosses are copies of bosses that you faced once already in the "basic" version of the game and are not necessary for game completion unless you want to have 100% completion or see all three endings.
When you first see that you are facing the Failed Champion you might be thinking to yourself.. oh, i remember this guy, he is easy. Normally he would be the first boss that you would see in the game many hours ago but this time around, whooo boy, he is much much much more difficult.
For one thing his attacks do twice as much damage, he is much faster than before, and there are things that will damage you that are constantly falling from the top of the room.
This is the ONLY dream boss I have succeeded in defeating and this took me probably 30 tries. The last try where I was sucessful I think it was more luck that having actually learned anything. When you watch YT guys that defeat this guy with zero damage it is easy to suggest that they are on a totally different level than the rest of us as far as gaming ability is concerned.
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The Soul Tyrant is the fight that convinced me that maybe I don't need all three endings and should just watch them on Twitch instead. This guy gave me a lot of trouble when I fought him in his "easy" form during the first encounter. Now, just like the Failed Champion, his is much faster, far more elusive and for me anyway, was very tough to avoid.
There are 4 dream bosses in total and quite a few that could be considered minor bosses which are far easier than the major ones. These are the hardest in the game by a long shot until we start looking at the 3rd ending which is reserved for only the most dedicated players in the world. I'm not even going to try going after Nightmare Grimm and the true final Radiance boss which is just absurd.
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Seriously, go watch a video of this boss encounter, it is a truly insane battle
I have never even seen the above pictured boss and based on what I have seen from other YTers and what they go through to get to it let alone defeat it in that prior to facing it you have to defeat every single boss in the game back to back before you even get a chance to face it. This can take an hour and if you make just a tiny mistake, it is back to the very beginning, I know that I will not be able to do that.
I do love the fact that they built this tiered system into the game though and it makes it possible for people of all skill levels to enjoy this absolutely fantastic game. It is a truly brilliant design that I think more games should incorporate. When a game is too hard across the board is discouraged casual players and "slightly higher than casual gamers" like me from every playing. If it is too easy the hardcore gamers have no interest.
Hollow Knight is the only game I can recall playing in my life that has the default capability of appealing to all 3 demographics.