A very good game, but not enough to quell the KH3 fever.
As stated above, KH 3D takes place immediately after KH2 ended. Sora and Riku are taking their Mark of Mastery exams, though as it's explained, it's pretty much for "being official" reasons. For their test, both of them are sent into the "world of sleep" to awaken seven sleeping worlds. Not much background is given about these worlds, or as to why they are asleep. Regardless, this predictably does not go as planned and Xehanort finds a way to muck things up once again. The story is classic Kingdom Hearts confusing, and unfortunately doesn't do a whole lot but bring the tale to another hanging end. There have been claims that it will transition right to Kingdom Hearts 3, but it could just as well turn into another add-on entry.
You are able to play as both Sora and Riku in this game, each with their own variant of the story within the same worlds. However, unlike Birth By Sleep, both stories are stored within one file and you switch characters using the Drop system. A small gauge will run down at a predetermined rate until it hits zero, upon which you will be forced into playing the other character. This rate can be sped up by negative status effects and slowed down with items, but cannot be frozen. You are also able to drop at will when not in battle. After a drop, you may select from a variety of bonuses for the next character using Dream Drops you collect, or convert them to munny instead. Overall, this system actually runs quite smoothly and prevents you from getting too far ahead with one character. No progress is lost when a drop occurs, except during a boss fight, which can be a bit frustrating but doesn't happen often.
In terms of gameplay, 3D plays a lot like Birth By Sleep, with a Command Deck loaded with special attacks and magic skills that run on a cooldown timer once used. In addition, both characters can use environmentally-based Flowmotion attacks that can be activated on a whim. When combined, these options can make for a wide variety of choices in combated, allowing you to build your characters as you see fit. Special "reality shift" events may also occur, allowing you to play touch minigames to gain extra damage, fling your opponent around, and so on.
Together, the above combat aspects provide for a pretty fun and diverse experience. However, there is one addition that trumps this all: Dream Eaters. Like the Heartless and Nobodies before them, Dream Eaters are the new menace of the sleeping world. However, they come in two forms: Nightmares that are you enemies, and Spirits that can be crafted from various materials and act as your allies. There are around 50 to collect, and they come in a variety of forms and specialties. The highest-end spirits, such as the Ryu Dragon, take a LOT of effort to craft, but it's incredibly satisfying to have these powerful allies on your side.
Spirits will level up and gain strength just like Sora and Riku, and the pool of creatures is shared by both characters. Your dreamy friends will grow through battle, but can also be raised by petting them and through a variety of training minigames. Among the points gained will be Link Points, which can be spent on a particular Spirit's "Ability Board" to open up benefits for Sora and Riku, such as stat boosts, magic resistances, and even special commands. Using these boards is vital in order to progress in the game, since a good chuck of Sora/Riku's strength will come from these boosts.
In addition, there's even a minigame called Flick Rush in which you can pit your Spirit team against another in a card-style game akin to Chain of Memories. It's simple, fast, and fun, and can be used to unlock medals that can buy a bunch of goodies in a special shop. There's a variety of CPU tournaments available, or you can play against a friend's team for even more fun.
If you haven't been able to tell already, the Spirit system is the stand-out aspect of Dream Drop Distance. You can easily spend hours upon hours just trying to collect and max out every spirit that's out there. On the other hand, this also highlights just how disappointing the rest of game is. While it's certainly a good game, it simply doesn't differentiate itself in any significant way from the rest of the series' side stories.
Although the worlds are all new, they are from a smattering of less-remembered Disney properties. The only particular standout is the Symphony of Sorcery based on Fantasia, due to its direct-from-the-soundtrack music and the supremely classic nature of the source. Others, such as the Tron sequel and Three Musketeers worlds, could just as easily been left out and the game would be none the worse. The only non-Disney inclusion are characters from The World Ends With You, which is interesting, but I don't think most people will know these characters, nor will they care much more about them after meeting them in this world. They don't carry the same appeal as more ubiquitous characters from the Square Enix properties.
In terms of visuals, the game looks pretty nice, just about the same as Kindgom Hearts 2. The worlds are detailed and colorful as usual, and Dream Eaters come in a fun variety of shapes and forms. The 3D effect doesn't add a whole lot to the experience, except for maybe some boss battles. Unfortunately, major slowdown does occur at times, but not generally enough to hinder gameplay. The game supports the Circle Pad Pro for camera support, but you'll be able to control them with the shoulder buttons otherwise. This can lead to some wonky angles that are partially mediated by enemy lock-on (which is quite reliable). Audiowise, the music is well composed and fits each world, as expected from the Kingdom Hearts series. Of note are the Sorcery of Symphony tracks, which are directly lifted from Fantasia and provide a nice change from the rest of the game.
The rest of the game doesn't stand out a whole lot. The gameplay is almost the same as Birth by Sleep, the bosses lack impact, the story doesn't tie up any loose ends, and the added mechanics (save Dream Eaters) don't add a whole lot to the experience. Everything works just as planned and runs quite smoothly, but just doesn't carry the same "oomph" that Birth by Sleep or the main series entries have had.
Dream Drop Distance is a solid entry in a series at an unusual point. As a result, while a very good game, it loses something when compared to its pedigree and in the desire for a for a full-fledged sequel. This will certainly be enough to hold the attention of die-hard KH fans (like myself) for a time, but you'll probably soon be left with even more questions and feeling just the same as before.