The way you kill heroes is through Dungeons' second big change. Rather than being an omniscient mouse cursor, you now have an omniscient avatar who you can level up through three different skill trees. You're by far the most powerful being in the dungeon (resembling Dungeon Keeper's Horned Reaper). Since you've got no way to order creatures around, you end up having to personally go sprinting up to any heroes that need to die (either because they're maxed out with soul energy or because they're starting to talk about how they first came to your dungeon before it was cool, or something) and fight them using a choice of cooldown-based skills and spells in a slightly tedious recreation of MMORPG combat.
Initially, this proves entertaining and engaging enough, but as the campaign's difficulty ramps up you'll notice the game weaving awkwardly and slurring its words like somebody who's going to be "drunk" in precisely one drink's time. One problem and I found this out on the first proper level, when several adventurers managed to go wandering merrily out of the dungeon with packs heavy with my damn gold is that it's hugely taxing to be both building your dungeon and keeping tabs on who your visitors are, where they are, what they need and how happy they are, not least because they're as unpredictable and easily distracted as, well, adventurers.
At worst, it's like playing a tower defense game in which you can't kill anybody and all the enemies are on strike. The sweet spot of letting your dungeon grind the heroes down, then swooping in to deliver a killing blow when they're on their way out is almost impossible to attain.
More often than not, you'll be looking for a new gold vein only to spot a satisfied hero mixed in with a grumpy one and a fresh-faced one. You've got no choice but to send your avatar running all the way from one side of the dungeon to this hot spot and engage in a lengthy fight with all three of them, kill the first two and leave the third by teleporting away.
And this is time that you should really be spending building, because Dungeons' pace is relentless. All the time, the heroes' levels are ticking up, and if you're not levelling up your own monsters, yourself and the quality of your dungeon, you're quickly up to your nostrils in hot water, and you know it.
The end result is a hard game that doesn't provide any of the transparency or precision that hard games need. The only way you're going to find out how to play Dungeons well is by entering the silent mosh pit of trial and error until you hit on what your priorities should be at which point the game's lack of content starts to reveal itself. What you can build more closely resembles a set of tools than a deliciously evil chocolate box.
I do feel obliged to keep comparing this game to Dungeon Keeper because it borrows so much that it looks like an appealing purchase for DK fans when that purchase could well be a mistake. Monsters are simply static defences rather than residents, and different creatures (five to each map) aren't attracted by what you build but simply become available when you capture one of their homes on the map. The range of rooms and clever tactics available to you doesn't feel particularly spacious, and while the game is funny at times, none of its creatures or characters will be finding a place in your heart. They're all simply numbers, obstacles or pains in your spiky, evil arse.
All of this makes Dungeons disappointing, but not necessarily boring. Dungeon Keeper's compelling core of carving a great, ominous complex out of rock and dirt is still partially intact, and Dungeons' vicious difficulty does at least add a perpetual tension to the game (as do a selection of game-ending bugs). It's simply hard to imagine anybody getting excited about Dungeons. I suspect this game missed its chance to be an underground hit in more ways than one.