These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
YMMV: Mushroom Kingdom Fusion
Awesome Music: Most, if not all, of the music tracks are remixed versions of the originals. Most, if not all, of the music is awesome. Mostly because they just took awesome music from other video games.
Complaining about People Not Liking the Show: Some of the developers of this game are known to get defensive and even retaliatory if anyone even mildly criticizes anything done in this game, whether it is level design or enemy placements. It's gotten better.
Demonic Spiders: The Flood corrupted Pansers are even more aggravating than their original counterparts due to how much faster and more aggressive they've become. They're dangerous even when alone.
Fan Dumb: The community had taken a downward spiral during and briefly after 2009, never dropping issues, being overly defensive against even the slightest criticism of MKF (even though the development team acknowledges the game has many flaws), and thinking their opinions are the only ones that matter. The zeal lead to fans adopting the opinions of the dev team as their own and fighting the critics in the name of the development team. The worst case of this was when overzealous Reactor member actually vandalized an article for the project on Encyclopedia Dramatica. It's gotten much better since then.
When it comes to independent, unrelated personal game projects of the developers, the fans will bother them about adding crossover elements, as if those games are offshoots of Mushroom Kingdom Fusion.
The Xeno Fighters EX remake took a stand. It will not turn into an MKF of shmups by adding random things that weren't from SHMU Ps (Pokemon, among other things). Zapdos was allowed to stay only because it was one of Judge Spear's nicknames.
Wart's Nightmare, the final level and the monsters of Super Mario Bros. 2 corrupted, decayed, and distorted by the parasitic Flood. Seeing what happened to the cute, cheery enemies is even more unsettling when they explode when defeated.