Like any of the games in the series, Diablo III is about one thing - the loot. "Beating" the game, as in defeating the final boss at the end of Act IV, gets you an achievement and allows you to play on the next harder difficulty. By no means is that the "end" of the game though. The default difficulty is normal. For the most part, the game is fairly simple and easily completed by yourself. With a level cap at 60, you won't even be close to max level by the end of your normal run through.
The formula for the game of the Beast III is unlocking the harder difficulties, play with three friends, and get all the loots - very Borderlands-esque (which took concepts from Diablo #fullcircle). The higher your level, the harder the difficulty, and the more people playing will account to you getting better drops. There are also items that add to your % pool for better items to drop. It's all about the gear.
Speaking of friends, like the other recent Blizzard games, you can talk to any of your Battlenet friends at any time. The social system is awesome and so simple it is downright stupid. On top of that, and perhaps the best feature, is that you can jump into any of your friends' games at any time (if there aren't four players in there already). The reverse is also true; your friends can jump into your game whenever. I personally love this feature. If I get a great drop that a friend can use, I just jump into their game, portal to them, and hand it over. That's networking baby. You have a stash which works as a shared bank for all of your characters. What I mean by this is that a sword you put in your stash, will be there for all your characters - not just for the character you put it in there for. This same system works for the crafters; the upgrade you get for the blacksmith and gem crafter are present across all your characters. Again, I am a huge fan of this system. Lastly, to break up some confusion, you can be both a blacksmith and a gem crafter. Also, blacksmiths make weapons for magical characters, as well.
The auction house is incredibly simple and efficient to use. Besides being a bit slow on searches at times, I have no complaints. You can sell up to 10 items at a time. The auction house is at the character select screen and nowhere in actual play. With that said, you have full access to your stash when buying and selling items. The categorization is easy, fast, and quite searchable.
The story line was surprisingly interesting with twists that I didn't see coming. The game revisits characters we have all come to know and love, with the addition of a few more. Blizzard did an excellent job of continuity and continuing the epic. In an action RPG like Diablo, I usually don't expect much from the story line, but I was certainly impressed.
There are five classes that can be played as either gender. There is zero customization with how your character looks however which is a shame, since I'm always a fan of customization. I understand character customization hasn't been a thing in Diablo's past and that I should be happy with the fact that I can play as male or female... but it certainly wouldn't have hurt, though. The only customization found in the game is done through dyes which can be bought from certain vendors.
Each of the five classes has their own skill set and different resource to use their abilities. For instance, the witch doctor has the classic mana system, while the barbarian uses fury. The witch doctor uses mana to cast spells and over time it replenishes, while the barbarian has to build up his focus through attacks to use his abilities - diversity. Unlike Diablo II, this game doesn't have skill trees. Instead, you build your character with a choice of six slots with various runes for each spell. Each ability you have has multiple runes that you can only pick one of to change an effect on that ability. Ability selection, rune selection, and what gear you wear determines your build.
Gameplay is similar to Diablo II but way upgraded (as expected) and definitely streamlined. There are more abilities, better graphics, and it's easier to jump in and out of games. There can only be four players in a game at a time, which is less than in Diablo II, but I feel like it is still enough. Although the game does not explain that there is more customization than is implied to your skills, by checking the Elective box in options, the entire skill bar can be customized however you want, not the way Blizzard predetermined it.
My experience with the game has been obsessively positive thus far. What I learned from my first normal playthrough were a few key things. Firstly, don't ignore vitality. It should be your secondary if not prime stat you want to keep up. Bosses won't care if you have low hit points and can one shot you if it is low enough. Secondly, and this goes along with the first, keep your gear updated. If you aren't getting the types of drops you want, go to the auction house and buy upgrades for cheap. Don't overpay for gear because in a few levels you are just going to swap it out anyways. Thirdly, change your spells and runes for certain areas/boss fights. For instance, if a boss takes more damage from lightning, use lightning instead of frost. Instead of using a rune that makes a larger AOE – use the rune that does more damage for boss fights. Lastly, know which way you came from. If you are running from mobs into unexplored areas, you will aggro more and die harder.
I feel that there are certain aspects of the game that are completely useless but only exist due to nostalgic purposes. The first of these aspects is the need to identify rare items. Once an unidentified item is in your inventory, all you need to do is right click the item and wait a few seconds. That's it. It doesn't require any sort of resource or item. The second are waypoints. Once you get the town portal ability very early in the game, waypoints become almost completely useless. Why use them when you can teleport back and forth using town portal feature at any time?
As far as the aggravating aspects of the game, there are only a few I've come across thus far. I assume it is an anti-piracy move, but only being able to play Diablo III online on Blizzard Servers can be a pain at times. If I lose Internet or their servers are down, I'm completely unable to play. I can't just play solo offline. There have been numerous times while playing that I'll just get randomly disconnected from the game and be forced back into the main screen. This wouldn't be a big deal except maps are randomized, which means upon resuming your quest, the map is completely covered again, and completely different. If you are towards the end of a difficult area or even a boss fight, this can be very very frustrating since you need to start the entire area all over.
Overall, I have to say I'm pretty impressed thus far - a week in and I'm still obsessively playing. The harder difficulties make for harder challenges and the need for better gear. The fact that the groups of three blue mobs getting new magical properties per difficulty level alone is challenging. They are by far the hardest part of the game in my opinion - vortex, jailer, shielding Hulking Phasebeasts are my NIGHTMARE. I died more to that particular random group than ANY boss in the game.
While Diablo III is a fun solo game, it really shines when playing with friends who have similar pacing rates. If you are a Diablo fan, a hack and slash dungeon crawler fan, an action RPG fan, or if a bunch of your friends have this game, I strongly suggest it. It's an easy game to lose track of time with or even just load up and play for 20 minutes. As a PvP fan, I am slightly disappointed with the lack of player vs. player action at release. Blizzard announced this long ago though, and they also said its coming; so we have that to look forward too.Happy demon slaying.