Arc Fatigue: Chapter V gives the player the in-game months of November and December to hang out with Alex's companions or go training in the Mind Dungeon before engaging the Climax Boss, introducing the calendar system that was never utilized prior. However, that's also more time than the player needs — they'll run out of meaningful hangout events and experience for the Mind Dungeon before the time period lapses. What's left to do, barring exploration to discover missed content, is to advance the days until the next event arrives.
The Golden Alpaca boss is...well, a gold-colored alpaca that can talk and has a penchant for saying "Lemonade!" Vella acts like it's a horrible monster. It's never explained what exactly it is, where it came from, or why it attacks you, and it's never brought up again once the battle is over. Even more egregious as this is a Mood Whiplash right after Rory talks about how his sister committed suicide and his resulting trauma.
When going to the sewers with Rory, there is a giant Soul Survivor in the sky. Our heroes never even notice it.
Eight Deadly Words: The main character is an insufferable dick who won't shut up and the rest of the characters, with the possible exception of Vella and Chondra, are either just as bad or as flat as cardboard. With how slow and prose-heavy the game is, it's very easy to stop caring about anyone in the game.
Ending Fatigue: After the party's loss against the Comet, the game devolves into Alex wallowing in his own self-loathing for a long while, followed by numerous confusing plot twists, which many felt dragged the game down. The fact that, from the Comet onward, both pivotal Final Boss battles are Hopeless Boss Fights doesn't help matters, either.
Ensemble Dark Horse: Based on LPs and reviews, Vella and Chondra appears to be the only characters that are well-liked, or at least tolerated compared to the rest of the cast, mainly for their more down-to-earth demeanor while also being the ones to consistently call out Alex on his thoughtlessness or rudeness.
"WHAT'S GOING ON!?"Explanation Multiple conversations in the game have ended up on the internet where most, if not all of Alex's dialogue just consists of him regularly asking what's going on, the most well-known example being the scene right before the Golden Alpaca fight, where even after Vella explains what's happening, Alex still demands an explanation as if Vella's entire spiel never happened.
The game's title. Officially it's supposed to be pronounced "Y2k", which almost everyone has universally ignored in favor of the more obvious "yeek" or "yick".
Overshadowed by Controversy: Many people became aware of YIIK due to accusations of the game using the death of Elisa Lam in a distasteful manner, making the scene based off of the case bloodier than it needed to be in addition to said scene being portrayed in a way that downplays the tragedy. Additional controversy came when lead voice actor Chris "Kirbopher" Niosi was accused of abuse by an ex-girlfriend. And then after that entire chunks of dialogue were found to have been plagiarized from Japanese novels, causing further controversy.
Padding: One of the main criticisms of the game is its sluggish pacing in its story and gameplay.
Gameplay tends to drag on due to the nature of the minigames used to attack in combat not doing nearly enough damage for the effort expended to do them, the Mind Dungeon being tedious to use, and the amount of time it takes to get from Point A to Point B on the overworld.
The Mind Dungeon, which acts as a physical manifestation of a level up menu, much like Fable III did with the Sanctuary and its menu system in general. It also carries over everything players hated about the Sanctuary, needlessly padding out basic menu functions, as well as forcing the player to level up one level at a time, even if they can level up multiple times.
Every attack in the game is carried out via a lengthy minigame which, combined with the fact that most attacks don't do very much damage, drag out fights for way too long. Similarly, when an enemy unleashes a Herd-Hitting Attack, you have to perform the Defend/Dodge minigame for every single party member, which adds to the length of battles.
Snark Bait: The writing comes off as an achingly self-referential take on the EarthBound format, with some extra themes being ripped from Persona 4 and poorly implemented.
They Wasted a Perfectly Good Plot: The game has an X-Files atmosphere for a large part of it, until the ending abandons it for a fourth-wall breaking meta story that involves the developers putting in a character from Two Brothers, their previous game.
Took the Bad Film Seriously: Even though Alex is largely considered an insufferable protagonist by most players, particularly due to his pretentiousMotor Mouth tendencies, Chris Niosi's delivery was usually praised as a positive point of the game (as well as the rest of the voice cast), most critics panning the writing in a vacuum as tacky and incoherent.
Unintentionally Unsympathetic: Alex is a pretentious, self-centered, and flat out grating hipster who constantly engages in poorly written Purple Prose and treats the whole world and his friends as though they revolve around him and his needs. Eventually, alternate versions of him destroy the world due to their negative personality traits consuming them, and in one ending he can choose to join them. While the character was not initially meant to be sympathetic, even while trying to atone for what his other selves did he comes off as just as self-absorbed and pretentious, leading to people cheering when he dies rather than taking the moment as the tear-jerking Heroic Sacrifice it was meant to be.
Wangst: Whenever Alex wallows in his own self-pity like after his loss against the Comet, which still makes him come off as self-centered.