Dungeon Defenders [$2.99] is an ambitious title full of carrots that propel a basic hack-and-slash experience. It also has systems and content out the wazoo, providing a level of good depth rarely seen in App Store titles. But as effective as its smoke and mirrors are, and as much as it has to offer, its controls and interface are a pain to use and navigate, making it hard to recommend.

A lazy bit of shorthand to describe Dungeon Defenders is “Diablo meets Tower Defense." Dungeon Defenders has the hack-and-slash appeal and the character classes from the former, and the tower building and flow of the latter. Overall, the two mesh into a good whole, providing a ceaseless stream of stimuli to play with.

You’ll spend more time hammering away at fantasy foes with the “action" button than anything else, but this basic offense is always in the service of defense of large, neon-blue crystals that sit in the middle of the game’s instance-based levels. These crystals have their own health meters, and if foes manage to pummel it to zero, it’s game over.

What makes defense manageable is the scripting and flow. A preset number of monsters amble out of spawn doors on scripted routes during each “Wave" of play. You can choose to confront these foes with weapon in hand or set up defensive towers via a character-specific radial menu. But maps are huge and enemies spawn in every possible corner, so towers quickly become the star of the show.

The placement of towers versus your decision to be in a certain place during a certain “Wave" is satisfying and rewarding. And there’s no shortage of towers. Each of the four character classes — the mage, the archer, the knight, and the warrior monk — have different spins on the same five or so towers, presenting some unique gameplay opportunities when coupled with the Rock, Paper, Scissors nature of the strategy you’ll need to consider.

Player-side, the combat boils down to basic hack-and-slash. Each of the classes do bring their own style of combat, which helps to mix it up, and the loot and grind lust that the game encourages with its constant drops keeps things interesting, too.

Dungeon Defenders has a neat online multiplayer compliment to the play and the characters are balanced in such a way to provide a rich experience. The catch is that the single-player balance is off, so you’ll need to get with some pals to push through the later levels.

For the most part, the network code appears to be stable. You’ll encounter a fair amount of latency and matchmaking oddness as you get into and attempt to find matches. And the lack of voice chat is annoying on a fundamental strategy level.

If the game controlled well, this would easily be a highly recommended game. Alas, the controls and interface are terrible. It’s painfully obvious that this is a game designed foremost and balanced for a dual-analog controller. Instead of integrating good touch-based controls, Trendy Entertainment has chose to just put all of a controller’s functionality up on the screen. It’s littered with buttons, bubbles, and dials to the extent that they obscure play.

But Dungeon Defenders is also fundamentally an awkward game to move around in, in part, due to the terrible 3D camera which needs to be babysat with an on-screen pad. As you can see below in the image of the game’s overlay, the camera control is not in a convenient or intuitive location, meaning you have to take your eyes and hands off the action in order to swivel the camera to a sensible spot. Also, a virtual d-pad for movement?

(Edit:  There’s a virtual joystick-less control option that you can turn on from the game’s menu, but it’s no good.)

Dungeon Defenders iOS is a deep, sometimes entertaining game… but the controls are a core, critical, nasty flaw that I don’t think can be “fixed" or addressed in any meaningful way. The game, quite simply, requires all the stuff the UI is lit up with. There’s a chance that if you’re the kind of guy who can play, say, Lara Croft and the Guardian of Light without issues, you might be able to get into this one. If you’re not, I’d stay away from Dungeon Defenders until it hits Xbox Live Arcade, PSN, and PC at some point.

Just a note: Dungeon Defenders is a Universal App. Playing on an iPad does reduce the UI clutter by virtue of being a bigger screen, but it’s still a mess and doesn’t alleviate any of overwhelming button overload going on here.