Path of Exile is a better sequel to Diablo II than Diablo III is.
PoE is a dark fantasy action RPG that looks and plays like Diablo, top down isometric view and a clickfest. But there are several things that set it apart.
There are 6 starting character classes that are based primarily on one of three stats (dexterity, intelligence, strength), or a hybrid of two stats. But that is just how you start. You can build that character into using any set of skills or items in the game.
There is no gold. Say what? The currency is items that are used for crafting, transmuting, identifying, or improving items you find and want to keep. Fairly useful currency actually.
In PoE you use flasks instead of potions. You don't carry around a stack of potions that you are constantly buying more of. You carry five flasks on your belt that can restore health, mana, and other special effects. These replenish automatically as you kill enemies.
The abilities you use come from skill gems that are socketed into gear. These can be removed. You can mix and match how you like. All gems that are socketed earn experience from killing enemies, regardless of what ability was used. There are other kinds of gems too, like support gems that when linked improve or change the way the ability behaves. This leads to some really cool possibilities.
The passive skill tree is HUGE! There are 1350 skills to chose from that add passive bonuses to your character. There are also notable and keystone passives that can really change how your character does things.
PoE is being developed by a small indie company in New Zealand. I'm a big fan of indie developers as they often bring new and unique ideas to market.
PoE is Free to Play! Entirely. The microtransactions they sell will not give you even a slight advantage. They are all cosmetic items or fluff actions.
The current state of the game is now open beta. Anyone can jump in now and there will not be another character wipe. I imagine they will use this time before official launch to continue to tune and polish the game, and add new features. but right now it looks great, is a lot of fun, and has really deep character development.