I am forever baffled by my fellow Sonic fans' willingness to overlook some of the most atrocious forms of media imaginable for the simple fact that their blue god is stamped onto the top.
Sonic Underground could have been a fun romp, an interesting take on the Sonic mythos with new characters and plots to further enhance the hedgehog's world. The premise: Sonic, his brother Manic, and his sister, Sonia, use the power of music to defeat Robotnik and find their lost mother before doom befalls Mobius. It's amazing! It ties in Mobius, it brings in the Freedom Fighters, it adds two decent siblings to Sonic (before two more infamous hedgehogs appeared in the series), and it carries Sonic's rock and roll vibe.
How can it fail?
Fail it did. Somewhere along the lines, the producers of the show found a wad of stale drugs.
Since I happen to actually *like* the more creative premise, I'd rather give this show a real, critical run down. First off, the dialogue is trite. It's less than typical '90s cheese, it's literally loathsome how poorly the show is acted and how poor the script is. Many of the episodes had the potential to be amazing, even classic, yet the script took the potential, stuffed it inside a blender, poured magma into that blender, and set the surrounding house on fire.
The sound design is equally poor. Very often, I found the background music cutting out abruptly, meaning that who ever edited the show had, perhaps, a few hours time to do their job.
This ultrapoor editing crosses over into the visual design. Far more often than less, you'll be looking at lackluster still images as the camera pans across the screen. Effects are added in for more dazzle, but it's cheap and very lazy. The animation is even worse, with almost all of it being rushed, sloppy, and sometimes flat out unfinished. Character expressions are weak and can, at times, even become inappropriate for the emotion we're supposed to be feeling.
The story, while interesting, has no impact on you whatsoever. It's the same drivel pushed out nowadays. "Treat kids like they're morons" This is made all the more disgusting by some wannabe mature plotlines that could have developed had it been in the hands of a more capable studio. This could have been the definitive Sonic cartoon of the '90s, on par with Batman: The Animated Series. Unfortunately, this symphony's flat.
At the end of the day, while there are good concepts and I'm sure some faint reason for the less mentally capable to like the show, no sane Sonic fan should even give this pile of smoldering garbage two glances. Most positive reviews for this show stem from blind devotion to Sonic sans any serious critical examination of the series.