Wow...I did not think this show could go from an absolute 10 in my heart, to one of the worst things I've ever seen.

For starters: Season 1 is flawless, perfect, I love it so much. The vibes are immaculate, the characters are perfect, the soundtrack slaps, it's strangely so comforting considering its dark themes, and it genuinely feels like a sweet home. I cared about all the characters, I cried when characters died, I wanted to know where the story would go, and I've rewatched it 4 times because I love it so much.

Season 2 went very quickly and steeply downhill. Hyunsu wasn't even in it, the monsters were nothing like season 1 and were instead generic stone things - and in the entirety of season 2 I think like MAYBE 3 people turned into monsters, which made everyone in the bunker feel useless for the story. It also hinted early on that the monsters aren't actually evil by showing the mom and baby monster, then completely dropped the idea a few episodes later (they weren't even mentioned in S3). They killed off basically all of the original characters from season 1 - which on its own made the entire season feel drastically different from the first, and it didn't even focus on the few characters that were left over from season 1 - Instead it focused primarily on the STUPID ARMY DUDES which I didn't care about in the slightest. And that weird lady in charge with her son in the basement (which was never explained or wrapped up AT ALL?!)
The only thing that I liked about season 2 was the fact that Sangwook was still alive inside of his body, but it wasn't even mentioned again for the rest of the season because HE WASN'T EVEN IN IT.
Also the soundtrack was so underwhelming - and by that I mean, completely unnoticeable. No Warriors, no Sweet Home, no Side by Side, no Monster Slayer...it was beyond disappointing.

Season 3 started out better than season 2 because "at least Hyunsu is in it." But when you actually think about it....no he's not. He's not acting like himself, he's not making any decisions of his own, he doesn't actually do anything to contribute to the story at all, and it never even properly explains what the hell is going on with him - that said, I am still glad Song Kang was at least in it this time, he did a fantastic job considering the horrible storytelling.
I was really excited for Eunhyeok to be back, but similar to Hyunsu's character, it wasn't really him - he had no emotions (literally), there was no heartfelt reunion with him and Eunyu (which was so anticlimactic after hyping it up so hard throughout the entire 2nd season), and literally nothing happened with his character at all. (Though I will say, the scene of him and Hyunsu fighting in the bus single handedly carried the entire season and is the only reason I rated this as high as I did.)
Throughout the season it kept having these "plot twist" moments that made it seem like we were supposed to be shocked but they were just the stupidest irrelevant things, like the fact that the pretty girl wasn't even actually the daughter of that crazy lady in charge...? And they just threw in the fact that the bad guy is Yikyeong's fiance and the reason he didn't recognize her in the first season is because he "didn't have his memories." It felt unplanned and rushed.
Also they killed off the remaining survivors from season 1 , save for the main characters, and Yeongsu turned into a monster (however, I did like that he became the same monster as his dad, that was a nice touch.)
The bad guy was working through the entire 2nd and 3rds seasons to go into his daughters body to be more powerful and blah blah blah, then he's in her body for all of like FOUR MINUTES then leaves and goes back into Sangwook's CRISPY FCKING BODY. Then Hyunsu cooks him over the fire like a fcking marshmallow and he leaves that body again, then some other stuff happens...AND HE GOES BACK INTO SANGWOOK'S BODY AGAIN (this time healed and beautiful, which I did appreciate) and the worst part of all is that it shows that Sangwook is alive and fighting inside, then the bad guy crawls BACK INTO THE FIRE and everyone just WATCHES IT HAPPEN?!?!?! ....so now Sangwook is dead?!?! After hinting at him being alive since the beginning and just destroying any hope that he could actually survive. He was fighting inside for over a year just to be burned in a fire...like what the hell, he's been through enough fire trauma and you end his story LIKE THAT?!?
And the daughter ended up having no purpose to the story at all. She just died...(I think??)

The ending of season 3 is possibly the worst thing ever...BUT, the thing that makes me even more upset is the fact that it WOULD HAVE BEEN A GREAT ENDING if the rest of season 2 and 3 were at all good. Hyunsu collecting survivors, humanity realizing not all monsters are bad and that they can coexist with each other - THAT is what I wanted the entire season to be about, that is what Sweet Home is SUPPOSED to be about - not irrelevant army dudes or creepy moms with monster sons or suspicious pastor guys or the creepy doctor or the daughter or neo-human-whatever-the-fcks. Sweet Home was supposed to be about surviving, and working together to create a "Sweet Home" to live happily. And season 2 and 3 were everything but that.

I still love every bit of season 1, but I will be completely erasing the last 2 seasons from my brain, and to me they do not exist canonically.