As the Earl of Lemongrab would say, UNACCEPTABLE!!!!?
Adventure Time: Explore the Dungeon Because I DON'T KNOW is WayForward Studios' second outing with the franchise, following the 3DS/DS game, Hey Ice King, Why'd You Steal Our Garbage?!!, which was a respectable Zelda II clone, if a little short. Here, WayForward has taken the old-school aesthetic and applied it to a dungeon crawler.
Let's talk about the good news first. The game keeps in line even more with the aesthetic of the television show than the prior one was. It has cut-scenes that are presented as moving 8-bit animatics, like the ones in the original Ninja Gaiden NES games, but with full voice-over by the cast of the show. This fits very well with the show's style, and on the Wii U, Finn the Human and Jake the Dog's living video game console, BMO, sits on the bottom screen and makes adorable commentary on the items you collect.
Storywise it feels very much like an episode of the show. Princess Bubblegum has captured a ton of dangerous criminals and placed them in a huge dungeon under her castle. But something strange is releasing the criminals, and it's up to Finn the Human (and an increasing number of playable characters you unlock) to beat down the criminals and find the source that's breaking them out. In standard Adventure Time fare it's handled with whimsy and a great deal of imagination.
I wish the same could be said for the gameplay, though. A top-down dungeon crawler with randomly generated dungeons, Explore the Dungeon isn't inherently bad. You can choose from a number of different characters with special abilities and different power moves to aid you on your quest, and the 16-bit pseudo 3D-style fits with WayForward's retro aesthetic, but it has some classic problems, like weird hitbox detection (especially with ranged attacks) and annoying enemy attack patterns.
None of this is particularly a dealbreaker at first. There are some changes to the environmental skins, with no real changes to function, and enemy types become more difficult as you go, which unfortunately become monotonous quickly. The gameplay highlights are the boss battles that directly reference episodes and characters of the show and often require context-sensitive actions. Destroying enemies or finding gold allows you to buy upgrades, and opening chests can grant you expendable character buffs that can be placed in a limited number of slots.
One major problem with the game is that the leveling and buff system are mismanaged. Leveling feels like you never quite have enough money for the upgrades you need unless you scour the levels for all the gold in them. You can only return to the game's hub where you can upgrade every five levels (getting killed means starting the five levels over from the beginning). Additionally, returning to the hub erases your character buffs, meaning you have to apply new ones you've found, which may not be as good as your old ones.
What is absolutely a dealbreaker is the crazy difficulty of the last fifteen levels. Even with the game being intended for local co-op, these levels are large, the enemies are harder to kill with annoying and more ridiculous patterns of attack, and it feels like a whole lot of artificially increased difficulty and map size to pad out the game's end. While the exploration of the dungeons is fine in the earlier levels, the size of them, with no map or hints towards locating the exit makes these levels both maddeningly tedious and difficult to negotiate. Even BMO's cuteness loses its charm after a while, though you can turn off it's voice in the options menu.
Adventure Time: Explore the Dungeon Because I DON'T KNOW! does a great job of managing and working with the story, characters, and feel of the franchise, but unfortunately doesn't have the gameplay to match, especially at a $40 retail price. If you're interested in the narrative and the chance to play as your favorite characters, wait for the price to come down to $15-20, more in keeping with the kind of downloadable title this game feels like.