They may have come out around the same time. They may both be ARPGs. That's about where the similarities end.
Customization
Remember making decisions about where stat points go? Remember when you needed to know more about a character than its class to determine what it would do and how it would play? Remember creating awfully inefficient characters which you enjoyed because they did something amusing?
It looks like all the customizable glory of its ARPG predecessors is here in Torchlight 2. You pick your stat points. You pick what weapons your class should use and which you shouldn’t. You pick what skills you have access to – and how many points to invest in each of those skills.
I play a Berserker this time through, and he’s been running with primarily a shadow-oriented spec, with some complimentary buffs from other trees. But – I’ve used some of the ice abilities for a level or two and come to the conclusion that I could (and may) create another Berserker later on down the line which would focus on dealing elemental damage. That makes 2 different types of characters which seem like they’d be distinct and fun to play without even taking a close look at the third tree (which has some things on it which seem interesting and I’d have to experiment to know if they were great or awful) – and after having very minimal experience playing the game. And then of course I have a ton of ideas for characters that have a high likelihood to be terrible (but that I may end up building nonetheless).
And if that isn’t enough skill customization for you, you also can use general purpose spells that everyone has access to.
Aside from that, there’s gear decisions for you and your pet, as well as many types of socketables and enchantments to keep your gear from being too dull.
Difficulty
Torchlight 2 can be hard. It’s really quite hard, if you want it to be. I play on Veteran, and I’ve come to the conclusion that I’m going to have to work on my in-game knowledge for a bit before I’m able to play hardcore. You can die very, very early in the game if you’re not careful – and I haven’t even tried the highest difficulty setting. This sound like any game you’ve played before? It sure doesn’t sound like Diablo 3, does it?
Torchlight 2 can also be easy, though. When I played on Normal, it felt something like an appropriate-leveled Hell Difficulty barbarian in Diablo III. That is to say – I could die, but I probably wouldn’t. And I imagine if you set it on easy… well, I imagine it’s pretty easy.
It can be what you want it to. If you want something which is horribly difficult to master – I imagine the highest difficulty will give just about anyone problems. But if you want something which you can play casually while joking around with friends - it can be that, too. The fact that difficulty is adjustable solves the problem of catering either to exclusively casual or exclusively hardcore characters – though I’ll be honest, the increased difficulty is the real draw here for me. There are other games I can play casually, but it’s been a while since I had difficulty on the non-highest difficulty setting for a game.
Gameplay
I mentioned already that it’s hard – what I haven’t mentioned is that it’s the “right kind of hard”. It was said of Inferno difficulty early in the lifespan of Diablo 3 that it was the “wrong kind of hard”. That is to say – the skill cap was relatively low, the number of skills you can use was relatively low, the damage was incredibly high, and player characters were incredibly fragile. I don’t feel this way in Torchlight 2. As a berserker, I feel like I have ways of healing and escaping damage, and ways of tanking damage too. In my brief experience with other classes, I haven’t had too much difficulty keeping them alive and avoiding damage.
A big thing here is potions – they work on the old Diablo 2 model. You take damage, you drink potions. You take more damage than you can heal in potions, you die. All classes have access to potions so there’s no need for some cutesy panic button ability so that you don’t die at times when you should be taking continuous damage.
Another big thing is skill diversity. I mentioned already that there’s a lot of room for customization. What I haven’t mentioned is that within each build a lot of skills and spells will be useful. My berserker is in Act II (at level 30-ish) and already he has 3 short-length buffs to keep an eye on and 4 summons. And then there’s the attacks. Needless to say, I’m never at a loss for things to do even so early in the game. The experience is that much more engaging because I feel like I ought to be playing it faster and with more of an awareness of what’s going on in the game.
And then there's this:
Item Acquisition
You get items from drops and friends. That’s all. No Auction House. Excess gold can find more than enough usage through enchanters and gambling – among other things – but there’s no direct tie between gold and items. It’s a much more exciting experience, and you get none of this:
http://www.teamliquid.net/forum/viewmessage.php?topic_id=354374
On this note, if you loved that loot wasn't shared in multiplayer D3, rejoice - you get the same thing here.
Statistical Complexity
Remember how easy figuring out gearing was in D3? Resist/ Vit/Main Stat well rolled on every piece – and that was all you had to know. It’s not quite so straightforward in Torchlight 2. Your choices often change in terms of optimality based on what skills you are using and how much your gear is lacking. There are also a TON of stats. There’s one for each resist, one for each stat, crit chance, crit damage, execute chance, elemental damage types, status effects, and I’m sure other things that I’ve forgotten to include. Depending on your setup, you may need only a few of these – or you might need all of them (I don’t see much that doesn’t seem to be of use to my Berserker).
Balance
Is the game balanced? I dunno. Probably not. But maybe that’s a good thing, because one thing the game is not is homogenous. Dex, Vitality, Focus and Strength all add differing amounts to each type of character – and while some skills are dependent off of high weapon damage, others are static based on level and elemental damage bonuses. That means that Strength, Focus, and Dexterity-based characters all take different amounts of bonus from their stats (both offensively and defensively) – but since when is that a bad thing? Do they all need to contribute to their character’s damage and survivability at exactly the same rate? I loved Diablo 2, and it wasn’t like this. I had fun with Titan Quest – same deal. The rules that Blizzard started applying to these types of games to balance them when WoW hit its stride really don’t apply here. It's not an MMO. Log onto Diablo 3 sometime (or don't) - you'll notice you don't have 50 people competing for your spot in your game.
Jeez, Diablo, you didn't have to be so blunt about it. I have people online, ok?
Sure, that means my Outlander might not get as far as my Berserker in Hardcore mode, but then it also means that the mechanics behind each of those characters get to be more distinct and interesting. In an ARPG, I personally find the latter to be much more important.
Conclusion
For those of you who quit D3 a while ago, or for those of you who are still playing but are wondering why you are bothering – Torchlight II offers a great and cheap alternative. There’s only a vague bit of story (i.e. some pit lord isn’t calling you names constantly, and you don't get to witness dramatic deaths of characters you didn't really care about to begin with), and the gameplay and mechanics seem rich and rewarding. I’m loving this game. Maybe it’s that it’s new (I’ll get back to you on that in a couple months). But for $20, I’m betting that I’m going to have my ARPG fix for at least several months – and if I’m lucky (and I can only hope I am) long enough for a new great ARPG to come out which ignores the direction that many of the ARPG games are moving these days. It comes highly recommended.
Just... close your eyes during cutscenes.