Much like Diablo 2

I can't get myself from playing this game, and this is my second day playing it, so that should give you some idea of what it's like.
Now for the serious review, this game will make you remember D2, or if you'd rather remember D1 that's ok too. From the moment that you start playing it you should get into the spirit of "saving the world from a dark and diabolic evil influence" and forget most of other RPGs out there. As an action rpg, you'll see your fair share of gridding but you won't really feel it as you'd feel it on other games since most of the grinding will be somewhat short, giving more of a "crude, this strategy doesn't work like this but I want to stick to it". It ain't really that well thought into, there aren't over 9k options for beating the same scenario, but it will help you a lot if you stop and think why some strategies aren't working anymore and how to do it right.
Fairly speaking, the first run through the game should be the most frustrating, simply because you don't know what to do and how to act and you will therefore believe that you need to grind and grind so you can get better (either items, skills or better hacks). But in the spirit of the Diablo, you'll get the option to play through the game again, same scenario and objectives, but harder monsters and better equipment.
If you don't want it you can always create a new character and easily transfer items to the new character simply by putting it on the chest.
With 3 characters to choose from, 9 types of possible dragons and a ton of options of items, including normal, semi-magical (because they aren't called so), rare (work as unique items but aren't so hard to find) and unique itens (harder to find than rare, working in a group kind of way in that the same unique item has 4 level variations, each one requiring 6 more levels than the previous one.) with the option of some items having sockets or not, 9 types of gems to fill those sockets or giving birth to your dragon and charms (items that just being placed in the inventory give you boosts), you will hardly have reasons to complain about diversity of options to customize your character.
On a side note, and a bad one at that, there are quite a few bugs in the game. Ranging from game-breaking (Rune Blades can't be manipulated at all! Avoid them like the plague) to sily (You can buy socketed maces for 30 gold and sell them for more than that, sometimes even thousands more), it might spoil the fun you could have had beating the game. (There are quite a few bugs actually: Sometimes monsters won't be spawn inside the map and so you can't beat the map and you have to "save and exit"; Dragons and Summoned monsters have strange damage dealing, sometimes the higher level ones showing lesser damage; some skills act in a bugged way, either giving you infinite hp (Necromancer Morphing), not working correctly because it's not linked to a target (Barbarian Rushing), not being able to hit targets because the target area somehow doesn't take in consideration the distance (Sorcerer Firebolt but also normal attacks for all the classes)).
All in all, if you work around these bugs (like always having your inventory filled so you don't pickup the cursed rune blade and lose an inventory slot, or doing a "save and exit" everytime you can't find that damned last enemy so you complete the map) you can have a real good time playing this game, which, like it's inspirations D1 and D2, is well worth playing!
On a side note, for those interested in hacking the game, you should be aware that most of the game parameters are root based.