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.
Badass Decay: Crunch started out as a gruff, musclebound bandicoot with a cybernetic arm who sports army pants and boots. He went from being Crash's defiant Evil Counterpart (despite being mind controlled by Cortex the entire game) who can change into powerful elemental forms in his debut in Wrath of Cortex... to being an annoying, Dumb Muscle Mr.T knockoff (In a BAD way) who spends much of his screen time blabbering Mr.T quotes and being useless in general from Crash Tag Team Racing onward, and is an utter wuss in comparison to his original depiction: He keeps a pink Teddy Bear stashed at his home...
Justified in that Crunch is attempting to atone for his past villainy by being a positive role model to children, if in a strange, haphazard fashion.
Let's not forget Tiny Tiger. Tiny started out as an angry, roaring monster who talked in hulk speak. As time went on, they started showing off his stupidity more for comical moments, such as in Crash Nitro Kart. And then in Crash of the Titans, he somehow transformed into a Bengal Tiger from a Tasmanian Tiger, got his intelligence upped, and began acting like a campy Mike Tyson knock-off who idolizes Crash, and only attacks him because he's hired to do so.
Broken Base: The fandom. Oh, dear God, the fandom. There are the fans who refuse to acknowledge any of the games not made by Naughty Dog and hate the later games, the fans who embrace the series as a whole, and those who only like the newer games and constantly hate on the Naughty Dog games.
Complaining about Shows You Don't Watch: The series receives this treatment a lot. Ever since Naughty Dog quit developing the games, people all over the internet have been saying "LOL CRASH SUX NAO!" but most of those people haven't actually played any post-PS1 era Crash games and are just complaining because the new games look different from the originals.
Although it doesn't seem to suffer nearly as much from this as certainother3D platformerfranchises... especially among people who considered the original games average in the first place, and thus have lower expectations.
Crowning Music of Awesome: Crash Twinsanity deserves special mention, as the entire soundtrack was done a capella.
But Wait, There's More!... Josh Mancell has outdone himself more than once, but what may be his greatest Crowning Moment of Awesome is when he composed "more-videogame-like" (as they had to be) tracks for the Japanese version of the first game (these) withinONEeffin' day!
Demonic Spiders: Bats showed up in later levels of the original Crash Bandicoot game in one of those really tricky, walls coming-in-and-out and floor-disappearing at random moments, side scrolling levels. Fortunately, these enemies were pretty much limited to the game's Scrappy Levels.
Sludges in Crash of the Titans. They are fast, do tons of damage, and do a near-impossible to avoid counterattack nearly every time you hit them, and they usually come in groups.
Battlers are also a pain in the behind, as they constantly block, come in large groups, and have a very powerful special attack which they love to spam.
TKs in Crash: Mind Over Mutant. They have ranged attacks which are impossible to avoid, a annoying melee attack that they are invincible while using and has a large area of effect, and can throw you off your titan.
Die for Our Ship: The moment Pasadena made a cutesy comment at Crash in Crash Tag Team Racing, all hellfire was unleashed in the fandom. Tawna finally reappearing the following game after (officially stated to have a fondness for Pinstripe) didn't help.
Discredited Meme: In Mind over Mutant, Cortex chastizes his minions for forcing "i can haz cheezburger", calling it a stupid meme. Guess he's not fond of Lolcats.
Dingodile is considerably popular thanks to his intro and being one of the few of Cortex's mooks who's not (as much of) an idiot.
Crunch Bandicoot is very popular, despite having no major role in the games since The Wrath of Cortex. The only reason he's even in Crash Twinsanity is because the fans begged for him to be put in.
Cortex is also very popular, and was also due to get his own game, Cortex Chaos, also featuring other villains from the series, but it currently seems to have been put on hold or even canceled altogether. Shame...
Most of the other villains are also incredibly popular, especially Brio, N. Gin and Tropy.
The Lab Assistants. It's revealed in Crash Bandicoot 3: Warped that they're all robots, but they look human by Crash standards in the first game. Their only means of attack (apart from standing there) in one level is to run at Crash with arms outstretched, occasionally generating electricity between their hands. It doesn't help that they return in Crash Bandicoot 2: Cortex Strikes Back, some assimilated into Borg-like space warriors, and the only way to beat them is to push them into a fire shield - and their standard cry is eerily cut off as they evaporate.
The Mount Grimly theme in Crash: Mind over Mutant is extremely dark compared to the rest of the otherwise cheery and upbeat soundtrack.
(The "Generator Room" level in the first game is particularly Nightmare Fuel-laden. Imagine an enormous, black space with exhaust pipes pumping what appeared to be black gas into the room, metallic platforms hanging over what appeared to be an infinite, dark void, and video screens brandishing a dead-eyed version of Doctor Neo Cortex's face throughout the area. The incredibly eerie and offsetting music does not help at all.)
Nintendo Hard: Crash 2 and 3 aren't by any means easy, but the original game takes the cake. The fact that you can only save in bonus rounds makes it even worse. Gems are also different in the first game:
Brutal side paths that hold little value besides some crates you need to break to get the gem for the level. Later games would have no crates on these paths and give the player a second gem instead.
You have to finish the whole level from start to finish in one life, including levels like Sunset Vista which may be longer and is certainly more difficult than any single level in the second and third games.
In the second game it will tell you how many you're missing just before the finish, and the third game keeps count for you during the level. In the first game, There's no sign of whether you have all of the crates at the end of the level, just a message afterwards saying "Great! But you missed 4 [of the most cheaply hidden] crates [of all time]".
Scrappy Mechanic: While Coco herself is a fairly popular character with fans, her playable appearances (which mostly play as a weaker variant of Crash) tend to be rather underwelming. Fixed somewhat in Mind Over Mutant even if you have to activate (and/or deactivate) the game's co-op mode to play as her, and playing the story makes a lot less sense.
A fair few of Wrath Of Cortex's vehicles gain similar critism, particularly the mech. Clunky, hard to manuever and easy to get hit as, it likely would have been easier and more fun to play the majority of the game as Crash himself.
That One Boss (Wa-Wa the Water Elemental in Crash Bandicoot: The Wrath of Cortex, Doctor Nefarious Tropy in Crash Bandicoot 2: N-Tranced, Doctor Neo Cortex in Crash Bandicoot 3: Warped, Madame Amberly in Crash Twinsanity, Uka Uka in Crash of the Titans.)
No, not Madame Amberly. That One Boss for Crash Twinsanity would be Dingodile. God knows I've seen enough complaints about it...
Both Tomb Time and Sphynxinator are somewhat hard, but rather acceptable given your progress: Tomb Time is only a bit harder than the other stages in the second world while Sphynxinator is very hard. However, the real offender is Tomb Wader, that just has to be one of the most difficult levels in the game, even considering the final tomb level, Bug Lite, that is set during nighttime. Simply put, Tomb Wader keeps filling the place with water (and we all know the way Crash deals with it by now) and emptying it back again. That level basically takes the S out of Scrappy Level.
They Changed It, Now It Sucks (The general opinion of the Crash games after Crash Team Racing, although the newer games are gradually getting better reviews.)
They Copied It, So It Sucks (Crash Bash and Crash Boom Bang! are considered to be bad Mario Party clones by many. Also, Crash Nitro Kart and Crash Bandicoot: The Wrath of Cortex are often seen as watered-down PlayStation 2 versions of Crash Team Racing and Crash Bandicoot: Warped respectively.)
They Just Didn't Care: The plot of Crash Tag Team Racing is very much this. Aside from making little sense by itself, the plotline has practically nothing to do with Crash aside from having several returning characters in it . The plot also ignores some things previously established in the series by having several Talking Animal characters running around for no reason whereas all the animal characters in the series are supposed to have been experimented upon and mutated by Cortex and other scientists. Oddly, the game seems to inspire less They Changed It, Now It Sucks complaints than Radical's later games, Crash of the Titans and Crash: Mind over Mutant, which are in every way much more faithful to the series.
This is arguably owed to the Radical games following a Rule of Funny depiction much more than the earlier titles. Titans is slightly more story-centric though Mind Over Mutant takes the random comedy Up to Eleven. All three games have met critism for such changes however, especially concerning the redesigns of the cast.
Villain Decay - It seems to get worse each new game...
Dr. Neo Cortex in today's games is nowhere near as malicious and sinister as his Naughty Dog depictions were. He and most of the other Doctors (notably N.Gin) are also a lot less intelligent and a lot more comical for a bunch of mad scientists now.
Played with in Mind Over Mutant. He's just as campy and deranged as ever, if not more so, but in terms of role, he takes revenge on his trecherous niece, overthrows and humilates his abusive boss and pulls an effective Not So Harmless Villain moment one on one fight with Crash, not to mention, lack of pants aside, makes a clean escape, avoiding his usual end of game Humiliation Conga.