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.
Anti-Climax Boss: Of course, as this is a parody of Gradius, the final boss in most games is incredibly easy compared to the levels right before it.
Ho Yay: Playing 2 players in Sexy Parodius will result in a "power up option" whenever the two players are together. This option varies from each character pairing (for instance, Vic Viper and Lord British will create a "wave" option which fires a wave attack that can be rotated via player position). Surprisingly enough, if one player is Toby and the other is Ivan, they produce the "love" option which fires homing hearts.
Older Than They Think / Sequel Displacement: Most people forget about the very first game in the series, titled simply Parodius, which came out for MSX in 1988, thinking instead that Parodius DA! (1990) from the arcades was the first game. Though when you see it, it doesn't exactly have as much widget value as the rest of the series does. It also isn't nearly as good and can be a bit more difficult than the rest of the series.
Porting Disaster: Parodius Portable is this for some, mostly due to some the music being replaced due to copyrights or possibly offending people.
Scrappy Mechanic: The powerup roulette mode, which wouldn't be so bad if it weren't for the existence of the !?/OH! "powerup" on the power meter, which nullifies every powerup you have. Woe the players who raged when they hit that so-called "powerup"...