Fairly polished for a game still in closed beta, Heroes of Neverwinter is tainted with only minor annoyances, such as over zealous sound looping and instances of glitchy animation between combat. The game also delivers many features that are much appreciated in any browser-based game, such as full screen mode, and the ability to zoom in-and-out during combat.
In terms of gameplay, HoN is a typical dungeon crawler: light on story, heavy on combat, and with a little bit of exploration thrown in. Built around a central quest hub (the city of Neverwinter), players are able to easily restock between adventures, and can choose from a range of level appropriate adventures.
Combat is quite faithful to D&D, and includes line-of-sight mechanics and a wide range of abilities. Like many adventure RPGs, the player controls a party of adventures either directly, or with the aid of AI. Combat is of course turn-based, and many abilities are limited to once-per encounter, giving fights a tactical edge.
While there is an exploration aspect to the game, it is quite limited. Dungeons will have optional rooms, and on rare occasions these rooms will sometimes require some exploration to find. For the most part though, the game follows a simple pattern: enter room, kill everything, collect loot, choose a direction, and repeat.
One of the most frustrating aspects of the game is the party system. Unlike most RPGs, you must rebuild your party before every adventure. It is clear that this was done to encourage the social aspects, but unless you have many friends playing (impossible during beta), it can get very expensive as recruiting party members costs gold. Add potions, and generally you make just enough each adventure to cover your expenses for the next.
The story aspects of HoN are poor at best. There is a story, including quest chains, but the writing is bland and adds little to the game. For the most part the story seems to exist soley to justify the locking of dungeons, with many dungeons accessible only if you have gathered items from other dungeons.
Achievements, quest rewards, and loot, loot, loot; HoN has all the features you would expect of a modern adventure RPG, but brings a social media twist to them all.
If you like designing and sharing D&D-style adventures, this game might appeal to you. If you like Rogue-like games, but want the experience compressed in to 10-minute chunks, this might be the game for you. If you like spamming your Facebook wall with fancy, but ultimately meaningless achievements, oh boy, is this the game for you.
Heroes of Neverwinter is actually a very polished Rogue-like casual D&D adventure, more than capable of delivering an enjoyable experience, and it is tempting to rate it quite highly on these merits. But there is always this unavoidable dark cloud hanging over you as you play: the game is designed to do everything in its power to market itself, to milk money from you, and to be a general viral pain-in-the-arse. You won't even get access to the game unless you "like" the game, give it permission to email you, and allow it to post on your wall.
If you are an adventure RPG fan, or fancy yourself a 'Dungeon Master', check it out. Just keep one hand on your wallet, and an eye on your fragile sense of privacy.