...I nearly lost interest when I finally realized that Shadow's in Sonic BOOM.
It's probably unknown to you guys, but I used to like Shadow the Hedgehog, that is until I realized that he brings absolutely nothing to the table in terms of character design and/or personality in comparison to other characters.
For Shadow to work, you have to remind yourself that he was supposed to be out of the game canon by his introduction game, Sonic Adventure 2. When he was reintroduced via bad writing in Sonic Heroes, I started to realize right then and there that SEGA only brought him back because the fans wanted him back. This was where his character started to become the very thing that most people (including I) that hate Sally Acorn so much about: He lost the potential to have the plotholes fixed up because SEGA had decided that it wasn't worth explaining, thus why nobody (including Rouge!) in the games ever bothered to give the rundown of what happened in Sonic Adventure 2 to Shadow when clearly the characters would be able to help Chip regain his memories. It was only when people started asking SEGA to explain what happened in between Sonic Adventure 2 and Sonic Heroes that SEGA decided to explain it: by making him half-alien of a generic 'want to DESTROY the Earth!' race in his own game, Shadow the Hedgehog. His character deteriorated by this point, making me realize that Shadow was SEGA's canon-made answer to Sally Acorn: A character whose personality and abilities are undefined yet is supposed to be this 'special' hero that has a lot of problems that supposedly get 'resolved' within a few years.
Of course, this is all just how I feel about the so-called 'Ultimate' Life-form right now. If you don't like how I feel then that's just a-okay. I just lost interest in Shadow when SEGA showed that they had no interest in making the character a character, but instead a face-plate for people who weren't satisfied with Knuckles and/or Metal Sonic in terms of 'opposite' rivals (which Shadow isn't, but I'll explain when the question's asked).