Ass Pull: Using Sunrise on Otohime causes her to transform into the Water Dragon for a brief time, despite her requiring the Dragon Orb in the first game to do so.
Manpuku. You either think he's one of the best partners due to his strong moral values, him trying to save his mother even before you meet him, and having a few awesome moments. Or you think he's the worst for being introduced right before one of the last dungeons, having inappropriate comedic moments, and having a disappointing power (the ability to travel across ice spikes, an ability that Kurow could've been able to do in theory as he can fly, and giving a fire source).
Waka retroactively became one due to reveals in this game, with some even think he Took a Level in Jerkass. Stopping evil? Awesome. Using Kurow as a doll/sacrifice to trap Akuro, leaving Chibi to kill him? Not so awesome. Though the game doesn't make it clear just how involved Waka was in this plan.
Kurow. After every previous boss being a relatively slow Puzzle Boss, this one is just a fast-paced slugfest that tests your raw combat ability. It's cathartic to just let loose with everything you've learned, amplified by the emotional tension of the fight. Also, Kurow's butterfly sword Laser Blade is just awesome.
The Final Boss, Akuro taking the form of a dark Chibiterasu partnered with a possessed Kuni, is a magnificent Mirror Match full of incredible fast-paced action against an opponent that can use their own Celestial Brush, similar to Ninetales from the first game but taken even further, with the DS' touchscreen allowing for a much more intense and fluid experience of fighting over the Brush. And dark Chibiterasu simply looks amazing, even before they become truly terrifying during the blackout effect.
Camera Screw: Since you have no direct control over the camera in combat, it's perfectly possible to end up in situations where you're blindsided by enemies or have a hard time getting what you want on camera to use a brush technique on it.
Captain Obvious Reveal: In an extremely minor case, it's very easy to tell that the little girl who asks Chibiterasu and Kuni to find her mother's mirror is actually Sakuya testing them in disguise.
Contested Sequel: In an interesting bit of History Repeats with Chrono Cross 12 years prior, Okamiden is frequently considered a good game in its own right, but its status as a sequel to the original Okami is hotly debated on account of the heavy liberties it takes with connecting itself to the first game's story, with a sizable camp of fans viewing said connections as overreaching to the point of delegitimizing much of the accomplishments made throughout the first game. These issues aren't helped by the fact that Okamiden was developed without the original creative team, which makes some of its more controversial decisions feel like conflicting creative intent.
Fanon Discontinuity: While many agree that it is a good game, some choose to ignore it as a sequel to Okami thanks to the time traveling shenanigans that take place halfway through the game that start messing around with the events of the previous game. One of the most infamous examples people bring up in regards to this is reducing Susano's Moment of Awesome and Character Development in the original game by showing he was scared shitless at the thought of fighting Orochi, and was about to run away like a coward before Chibi forced him into confronting him, regardless if it meant his loved one would die as a result.
Goddamn Bats: Thunder Ears are widely reviled for how long it takes to defeat them. Their electric attacks can stun Chibi, which can be problematic if they are fought in a group. Compared to their counterparts, the Fire Eyes and Ice Lips, the Thunder Ears' weakness, the Galestorm brush technique, is only available relatively late in the game compared to how early you are forced to fight them. Until then, you are forced to wait out their attacks until their shields let up and they become vulnerable. They also have an annoying attack where they can form a thundercloud that rains down thunder balls, which can only be removed by using Galestorm.
Only the Creator Does It Right: The game had no involvement from any of the key members at Clover Studio, and the game's reception echoed that to an extent, with its flaws being blamed on this aspect.
When you're told that everything you've done the entire game has been helping Akuro, even if you delayed the inevitable by slaying Orochi 100 years ago.
Seeing how the Goryeo sank (which is the sunken ship from the first game).
Seeing Shiranui die onscreen, with all the villagers and his grandson sobbing.
The granddady of them all in possibly both Okami and Okamiden: Kurow's fate and how he sacrifices himself to kill Akuro, with Chibi and all your other human partners absolutely bawling as they try to convince him that even though he was a living doll clone of Waka, he was still a different individual. Cue the crying when "Everything Must End" plays as Kurow's life slips away from his body.
Ink only regenerates in Easy Mode; for those looking to challenge themselves in Hard Mode, it leads to frustrating moments where trying to solve puzzles leads to Chibi getting nerfed. To compensate, enemies drop ink pots far more frequently than they did in the first game.
There's only one save file. After finishing the game, you'll either have to play the New Game + or erase your data.
Unlike in Okami, "important" collectibles (those required for 100% completion) such as Fetch Quest items and the Issun Masterpieces become Permanently Missable Content if you don't collect them before their respective areas get locked off. This leads to a lot of frustrating Guide Dang It!, especially since this design decision was completely avoided in the previous game.
Scrappy Weapon: Rosary weapons are flat out terrible. Compared to Okami, Rosaries deal a lot less damage and take longer to hit enemies. They also can't auto-lock onto enemies within range. The fully upgraded version, the Mystic Beads, fares a bit better due to dealing good damage and having the potential to stun lock enemies.
Tainted by the Preview: Some people were very disappointed to hear that this game was to be on the DS.
That One Attack: Akuro's ultimate attack during his first form, where he charges a laser, while attacking you his giant hands. What makes this difficult is that if his hands grab you, they will likely not let you go until he fires his attack, which not only take away half your health but also heals him. This means that any damage you've dealt will be fully healed if he has more than 50% of his health remaining.
That One Boss: King Fury, who wouldn't be too hard to fight if you didn't have to leave your partner vulnerable so they can keep the arena from becoming a hazard. Because they're at the controls keeping the mech below from attacking the arena, they're vulnerable to King Fury's attacks and must be directed away from them with Guidance, but being away from the controls for too long can get them hurt if the machine activates again. Having to manage your partner while slowly eating at King Fury's health is a serious challenge. If you haven't perfected Power Slash by this point, he is probably one of the hardest bosses in the game besides the final bosses. The saving grace of the fight is that you are able to heal your partner by picking them up. The fight would be nearly impossible otherwise.
That One Level: The underwater sidescroll in the Sage Shrine due to the annoying instant game over if you fall behind even once.
Visual Effects of Awesome: Despite having none of Okami's original developers, the team did a fantastic job of recreating its art direction on the DS's low-grade hardware. The Guardian Sapling scenes in particular have lost minimal splendor in the transition.
" plays as Kurow's life slips away from his body.