Torchlight is the debut title from Runic Games. Now, if you don't pay much attention to industry news, then you might not know anything about Runic Games, but suffice it to say that they're where about half of Blizzard North ended up, after a short detour through Flagship Studios. Since Blizzard North was responsible for the first two Diablo games and Flagship Studios for Hellgate: London, it should come as no surprise that Torchlight is an action role-playing game. What might be surprising is that while the game is polished and entertaining, it's pretty content to be a Diablo clone and nothing more.
In Torchlight you control one of three characters: an alchemist (magic specialist), destroyer (melee specialist), or vanquisher (ranged specialist). These characters are defined by their strength, dexterity, magic and defense, which do about what you'd expect, and each class also gets 30 skills of 10 ranks each. About half of these skills are shared amongst all of the classes, but the other half help to make the classes unique. Each character also gets a pet (either a cat or a dog) to help them out.
At the start of the game, you learn that something bad is going on in the ember mine below the town of Torchlight, and you then spend the rest of your time delving deep into the mine and the ancient caverns beneath it, until you face off against a big, bad boss named Ordrak. There isn't much in the way of story or dialogue or twists and turns -- unless I missed something, the game doesn't even bother to define what Ordrak is supposed to be -- you just have to be content to explore dungeons and kill lots of monsters (including zombies, goblins, trolls, and dragons).
Control in the game is very simple. You left click to move your character, interact with objects, and attack, and you right click to use a skill or spell. The game allows you to define some hotkeys for selecting skills, spells, and inventory objects (the function keys and 1-0 keys are all available for this), and there are even some niceties, like being able to press TAB to switch between two skills, and W to switch between sets of weapons. You can also press ALT to highlight items on the ground, and SHIFT to fight without moving. If this paragraph sounds familiar, it should -- Torchlight uses roughly the same control scheme as every other point-and-click action RPG since Diablo II, which makes sense. It's fine to use what everybody else uses if it works and it's convenient, rather than to create something new just to be different.
Of course, Torchlight does have some unique features. Your pet, for example, adds inventory space for you, and it can wear jewelry and learn spells (most of the spells in the game are found rather than appearing in a skill tree). Torchlight also has a clever system for enchanting equipment. For a modest fee, an enchanter will add a random bonus to an object for you, but each enchantment also comes with a chance of total disenchantment, and this chance grows with the number of enchantmentss you add. For most items, it's pretty safe to enchant them four or five times, but after that the item gets useful, and the chance for a disenchantment grows to about 10%, and you have to decide how risk averse you are.
The main dungeon that comes with Torchlight consists of 35 levels, and you get a new theme after every five levels (so the undead levels look different than the goblin levels, for example). The enemies in the main dungeon are fixed, with Ordrak always being level 30, but there are optional levels you can visit, including (I think) an infinitely large shadow vault that opens up after you've defeated Ordrak once. That means you can keep playing your character for about as long as you'd like, and it also means you can adjust the game's difficulty on the fly. If the monsters in the main dungeon are too tough for you, then you can hit some optional levels for a while and build up your strength.
Torchlight comes with four difficulty settings (from "easy" to "very hard"), and it also has a hardcore setting (where your character can only die once). I played three characters through the campaign, each with a different class and difficulty setting, and while I was disappointed that the classes felt a little too similar (the biggest difference was the weapon they chose to specialize in), I found the game to be generally enjoyable. There are lots of items to find and monsters to kill, and the difficulty scales pretty well with your character level, so the combat never gets dull.
Unfortunately, there are no choices to be made during the campaign, the main dungeon appears to be relatively fixed, and the optional levels just use random themes and monsters from the main dungeon, and so Torchlight requires a certain amount of forgiveness for repetition. But with a suggested retail price of only $20 (plus frequent 75% off sales), and 40-50 hours of gameplay even if you don't decide to take a character to level 100, Torchlight is a great deal, and it's a nice enough option if you have some free time that you don't know what to do with.