- Base-Breaking Character:
- You either find Amanda hilariously dark and entertaining, or annoying and poorly written villain with hideous design and annoying voice (despite being voiced by Kari Wahlgren), the facts that her hatred toward the beasts is unexplained and she had nothing to do in almost every episode but hopelessly trying to get rid of Bunsen don't help.
- Mikey and Bunsen themselves are either lovably awkward or insufferably annoying.
- Broken Base:
- The show as a whole has received mixed reception from audiences. Some people enjoy the show for its unique art style that it has for a Butch Hartman show, with some even considering it to be a return to grace for Hartman following his recent decline in popularity. However, others had been rather negative since the show might get annoying and repetitive. It doesn't help that it has the same writers (and Flash animation style) from the not so well received 10th season of The Fairly OddParents!. While the show has yet to receive massive hate, reception varies from very great to not as good as Danny Phantom but much better than T.U.F.F. Puppy and modern Fairly OddParents.
- The Crossover Episode "Beast of Friends" with The Fairly OddParents is either a funny and enjoyable episode, or tasteless and weak crossover with a huge Series Continuity Error/Ass Pull for the latter shownote , and Timmy's Dad's unnecessary appearance doesn't help at all.
- Ear Worm: The theme song. Not a bear and not a yeti!/Many hands to eat spaghetti!
- Hilarious in Hindsight: Kari Wahlgren playing Amanda, a Fantastic Racist and Manipulative Bitch, is this considering the last character she played in a Butch Hartman show is more or less the complete opposite.
- Moe: Mikey, along with Bunsen, are both yet another example where a Nicktoon stars a couple of good-hearted children with cute expressions, Adorkable quirks and a close bond with each other; Nickelodeon seems to be on a roll with this trope.
- Tough Act to Follow: Given by the fact, like among each show made by Butch Hartman (except The Fairly Oddparents' first five seasons and Danny Phantom's first two seasons), this one seem to fall right at the bottom of the category, as many did see some improvement over its predecessors, but it wasnt enough to match all of the other shows in terms of gathering attention.
- So Okay, It's Average: While Bunsen hasn't reached the popularity of The Loud House due to its mixed reception (see Broken Base above), it's still considered an overall improvement from Nickelodeon's previous animated shows.
- Ugly Cute: Most of the characters.
- What Do You Mean, It's Not Political?: A plot about a kid who's much different than the rest, is part of a group that is in need of acceptance and deals with one who opposes him because of that fact and tries to stop him from achieving the right to be treated as everyone else in society... gee, why does that sound familiar?
- The Woobie: The poor ice cream truck salesman. Good thing that everything ends well for him.
YMMV / Bunsen Is a Beast