I think the biggest reason that Halloween Horror Nights XX is often spoken negatively of has more to do with the false billing of the event than the event itself. HHN XX was being hyped up as a celebration of the past 20 years. It was hyped as the big and bad 20th anniversary of Halloween Horror Nights. They even had the fantastic idea of bringing in what could (and should) have been their biggest and baddest icon yet. Things seemed like they were coming together for one hell of a Horror Nights celebration.
However, the event ended up being nothing more than another regular Horror Nights year. There was really nothing celebrating the 20th anniversary outside of the Hallow'd Past house and the Twenty Years of Fear scarezone. Even worse is that Hallow'd Past wasn't a good house. I know some people might have enjoyed it, and to be honest I did enjoy looking at the props in the warehouse sections. Hell, it was honestly a great idea for a house. But at the end of the night, there were only 5 or 6 former houses represented in the event, and most of them were fairly recent (Scary Tales III room, Dead Exposure rooms, etc). I left that house feeling extremely underwhelmed at what they did with it. Twenty years worth of material to work with and we're treated with rooms from houses that are only 4 years old to begin with? That's a horrible idea and horrible execution. Not only that, but this should have been the house representing Fear. Every icon needs to have a house to help better establish themselves as the icon for the event. Or at the VERY LEAST have a scarezone themed after them. Fear didn't have that. Hell, Fear didn't make but one appearance at the entire event and he wasn't doing much other than standing in one spot.
So in short, I think the poorly done Hallow'd Past house along with the badly executed attempt at Fear are what helped screw up the reputation for this year. It's a real shame to because the entire premise for Fear was well crafted and had a hell of a lot of potential. He was just very badly done. Bloody Mary is STILL remembered to this day as a great icon for Halloween Horror Nights 18 because she was AMAZINGLY well done. She had scary commercials, she had a complete back story that was told entirely from the Horror Nights website, she appeared in a very nicely done opening gate video that really helped to make it seem as if we were entering her realm, and she even made several guest appearances in the other houses as well (I recall seeing her in The Hallow and Creatures, for example).
In short, the few houses that were nicely done weren't enough to save the year from the poor execution of Fear. The event was far too hyped up for what it really was, and it really didn't feel like a 20th anniversary of Halloween Horror Nights like it should have. Hallow'd Past, which was largely though of as the "end all be all" of Horror Night's houses was fairly mediocre compared to what it should have been. That's HHN 20 in a nut shell.
