Audience-Alienating Premise: While the series had moderate success and even an animated series, the problem was that it failed towards both age demographics. Most teens and adults were turned off as it looked too kiddy, while many kids were turned off because the micromanagement was too complicated.
Demonic Spiders: Sour Crowlas are normally benign compared to other sours. However, if one comes into your garden and you have a sick piñata in there at the same time, smash it or scare it away fast. They're effectively mini versions of Dastardos when this happens.
Even Better Sequel: Trouble in Paradise, for introducing a greater variety of Piñatas to find, having an actual reason to catch all the Piñatas in the challenge system, and simply for having far more content then the first game.
Some Ruffians have brown-colored tattoos on their hands and feet. At first they seem to simply add to their nastiness, until you realize what Ruffians probably do to captured piñatas filled with chocolate.
Pigxies are the sworn enemies of Rashberries and Swananas. This could suggest they're horrified of what they have created.
Game-Breaker: The Wishing Well in Trouble In Paradise. Throw in 1000 Chocolate Coins, and you're guaranteed to receive several coins worth 2500 each in return. And the value of these coins can be increased by up to five times just by placing a cheap item in the garden.
All sour Piñatas; they spit poisonous candy in your garden, and they'll keep coming back until you're able to tame one.
Whirlms, requiring only a small patch of dirt or grass to settle in, are guaranteed to automatically join your garden every now and then. If you don't get rid of them, they'll be followed by Sparrowmints. Luckily, you can easily get rid of Whirlms if you have Fudgehogs visiting.
Any undesired Piñata qualifies. They might eat your fruit or hunt your resident piñatas in order to stabilize themselves, whether you like it or not. Said unwanted residents might also scare off or start fights with other Piñatas. The only solution is to brutally smash unwanted visitors with a shovel to keep said species away for a while. This is fixed in Trouble in Paradise, where you can set the Bouncer Board at the corner of the garden to repel a given Piñata from showing up at all, but only if you've already got the Master Romancer award for it. Fixed even better in Just for Fun gardens, where the only requirement is that you've had that piñata as a resident.
Good Bad Bugs: In the second game, it's possible to keep Professor Pester out of your garden by building a wall across the side where he normally comes in. Normally, he stops for a moment, makes a couple futile attempts to get past the wall, and then leaves. However, due to a bug, it's possible that he will get stuck there indefinitely, even if the wall is removed. He still makes idle noises, but it's definitely an improvement over him wreaking havoc.
Jerkass Woobie: Dastardos may be a jerk who kills sick piñatas, but he was taken from his family against his will and turned into a husk of his former self by Professor Pester. Not to mention no one knows who he actually is, so he'll probably be estranged from his family forever...
Pocket Paradise has the themes for the sour Piñatas and Dastardos. These themes sound like they came from a 90's slasher film. In a Viva Piñata game.
The aforementioned Sour Crowla◊. It has a massive, razor-sharp beak with jagged protrusions. Additionally, its maw is so huge you can see the organic, wet-looking back of its throat. In a game where all the animals are made of paper, it's quite jarring.
Player Punch: If you've grown close to one of your piñatas, maybe named it and dressed it, you might feel badly hurt if they get smashed.
Squick: The game doesn't keep track of families, so not only is BrotherSister Incest a possibility, but you can even mate Piñatas with their own parents or children. To be honest, there's so much inherently wrong with the game that there's even a VG Catscomic that sums it all up nicely.
That One Sidequest: Some of the requirements for making a piñata a resident can qualify. The Chippopotamus is particularly terrible. First, you need to have it visit by covering half of your garden with water and having 15 of each water plant. then you need to add another 10% of water and feed it 10 of said water plants. Then there's the romancing requirements, which are borderline Noodle Implements. You need another 10% of water, a Candary Master Romancer award (which means you need to romance Candaries 5 (3 in Pocket Paradise) times before being able to romance a Chippopotamus once), have at least 1 Candary, and then feed the Chippopotamus four Birds of Paradise. At that point, you might as well use some Romance Candy, as it's just not worth the struggle.
Flutterscotches. The white ones aren't so bad, but there are nine other colors, each with their own Romancer and Master Romancer awards. Not helping matters is that all baby Flutterscotches hatch white regardless of parent color, so you have to evolve them individually for the latter. Plus, the flowers required to get some of them (particularly orange and brown) are unavailable until much further into the game.
A lot of Piñatas based on non-traditionally cute animals, such as Tafflies, Reddhotts, Cocoadiles, Shellybeans, Syrupents (and their off-shoots, the Twingersnap and the Fourheads), Whirlms, Crowlas, etc.
A lot of Sours count considering they're supposed to look menacing, especially the Shellybean, which looks like an evil Gary the Snail.
Designated Villain: Langston Licktoad. He's indeed always trying to catch Fergy (and Paulie) and force them to go to parties where they'd be smashed up, but it's just his job. It's not like they won't be repaired when they get back to the island.
Fergy and Paulie in the animated series. After all, can you honestly blame them for not wanting to get beaten to a pulp?
Langston's not a bad guy and doesn't want to cause trouble, he's just trying to do his job and get a simple paycheck. Seeing as every Pinata (not counting Fergy and Paulie) sees it as an honor to go to parties, he believes he's doing a service, and if he doesn't get the two to comply, his bowl of fruit boss starts to question his wrangling skills, and could fire him at any time. Then there is the fact that he literally has no friends because of his "stick-in-the-mud" attitude