There are plenty of reasons the movie was terrible.
Superman, Batman, and WW themselves were alright. Lex and Doomsday were absolutely wasted. I've always said a super hero movie is only as good as its villains, and BvS tanked in that regard. The plot was also pretty weak. The way Lex set Bats and Supes against each other flat out shouldn't have worked. It was a sucky reason to have them fight. Doomsday being shoehorned into the movie when they could have saved him for an awesome DoS movie was a terrible choice.
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Kryptonite being pulled out as the plot device is such an old trope for Superman too. Snyder went on record to say that Kryptonite doesn't exist in his universe back when he made MoS, and then he did a 180 here to give a lame fight between Supes and Bats. Even worse, he made Kryptonite Doomsdays weakness too, which doesn't make sense since DDs powers are to evolve to overcome his weakness. Kryptonite should have been no different. It's just radiation after all. This is what killed most of the action scenes for me, and killing the action scenes after already building an abysmal plot was a terrible choice.Also, this was a Batman movie. We followed Bruce/Bats for the majority. Supes was a side character no different than WW, which was annoying since it's his movie with his villains.
Why did Lois throw the kryptonite spear into the water only to get it back later? How did she know it was DDs weakness? She wasn't there when Bats figured it out, and had no idea DD was Kryptonian.
Why didn't Bats go grab the spear? That was his entire plan, and why he brought Doomsday back towards the city like an idiot (isn't this exactly why he hated Supes at first?). Then he just stood there and watched for the majority of the fight, completely oblivious to his entire plan with the spear. He was pointless for the entire last fight. This is not how you use Bats in the Justice League.
What was Lexes motivation? He had no reason to target Supes the way he did. Maybe he was just crazy, but thats not Lex. I couldn't take him seriously at all. Also didn't like how easily he played Bats.
How the hell did Lex frame supes in the beginning for killing the people of that village? They died from freaking bullet wounds. Same with suicide bombing. That obviously wasn't supes. He doesn't have the ability to just explode, and would have no motivation. No one would actually think Supes committed these things.
Batman was just flat out murdering people in this. What happened to his no kill rule?
WTF was with that scene where the Flash goes back in time to warn Bats? Thats cool and all, except it was a dream. How would Wayne dream about the future? He also somehow had premonitions of Darkseids invasion, which is a weird ability to give him.
How did Supes just not hear his moms location? She was crying against the gag. He can hear Lois halfway across the world to stop her from being shot. He can hear her screaming halfway across the world, get suited, and fly back to metropolis in the seconds it takes her to fall from the top of a skyscraper towards the ground (and reach her before she gets halfway to the ground). Why couldn't he do the same for his mother?
I also didn't like Supes automatically accepting that he might have to kill Batman to save his mom when he talked to Lois. Thats not Supes at all. He wouldn't get played that easily.
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