Armies meet in fierce battles on the surface level while smaller groups of heroes explore the ruins and dungeons below. A pair of mini-maps makes it pretty easy to keep track of things and switch between the two environments.

Not much has been released about the story behind the game yet, and the preview I played was multiplayer only. It's clear, though, it has much to do with the magical world of Eberron and three warring factions battling for control over an artifact of ultimate power: The Heart of Siberys. Each faction has a very distinctive look for the buildings and for the units, but aesthetics are not the only difference. Each faction's units are different, yet well balanced.

The Order of the Flame is a faction devoted to battling the forces of evil. It consists of humans and dwarves and elves and what are probably the most recognizable unit types for D&D fans. This is the faction of barbarians and rogues, clerics and paladins.

The Umbragen are evil, shadowy figures, descended from ancient elven races. The units available are all quite dark and sinister. Tainted priestess, dread knights and blood reavers.

Finally, the Lizardfolk are a tribal society of reptilian races. Their central 'structure' is actually a massive dragon, The Great Mother. Units include the spitting turtle, the tribal shaman and the pteradon rider.

Dragonshard dispenses with or re-imagines many aspects of real-time strategy that some people might consider staples of the genre. Resource gathering exists, but in a completely new way. Base-building and layout takes on a new, important role, while the tech tree aspect of most other games is discarded entirely.

Instead of having a 'peon' unit class to gather gold and iron and wood and such, the only resources are gold and 'dragon shards', both of which are acquired by all units through adventuring. The dragon shards are found scattered about the landscape, the result of frequent meteor-shower-like events. Gold is found in the depths of the ruins below, guarded by terrible monsters and deadly traps.

One of the most unusual and intriguing features of the game is its approach to base-building. Each player's main base consists of a large central structure surrounded by four grids. These grids are the building sites for the base's buildings. There are ten different buildings available to each faction and each building produces one unit type.

What makes this interesting is that each building has a certain bonus that it applies to all units created at the other buildings within the same grid. A barracks gives a +1 bonus to armor while a mage tower increases mana regeneration. The bonuses stack, too. Barbarians created from one of four barracks in the same grid will have four times the armor bonus as if there were only one barracks.

Additionally, every building adds to the player's maximum unit count. It's essential to build as many buildings as possible, even several of the same building and even if some of them are never used to produce units. The more buildings, the bigger the army. On the other hand, having fewer than the maximum number of units has an advantage as well. A slow trickle of resources is awarded as a form of 'tax'. The larger the unused portion of the population cap, the larger the tax revenue.

These features allow for a large amount of flexibility in play style. Players who like ranged attackers can create an army based on them and arrange their base in a manner to bolster the units' effectiveness. Another player might create an army of magic users with armor bonuses.

For another new twist on the RTS genre, there are four classes of units. Champions are the hero units. Expensive and powerful, these units have names and (presumably) play a role in the single-player campaigns. Each has several very powerful abilities and attacks.

Commander units are the bread and butter. Each has a very specific role, such as the cleric for healing or the rogue for picking locks and disarming traps in the dungeons. These units can be upgraded or 'leveled up' by spending the experience points earned through combat. Another aspect of base layout comes into play here. The number of upgrades available for each unit is also determined by building placement. Build several of the same type of building and the units created by it can level higher.

As the commander units gain levels, they can recruit subordinate units to follow them into battle. For instance, a barbarian can have several fighters as followers. A mage can have apprentices. This third tier of units fills out the ranks, tripling or quadrupling the size of an army.

A fourth class of units are hulking siege units that endure and deal massive damage on the battlefield.

Only champion and commander units can venture into the dungeon areas. These parties of adventurers have an important role: gathering treasure. The dungeons are the only source of gold and they also hide some other important artifacts that provide significant bonuses to the army above, such as increased experience or nullifying the enemy's armor.

These treasures and artifacts are well guarded. Dragonshard's dungeons are filled with myriad monsters that any Dungeons & Dragons fan will instantly recognize, from iron golems to the shambling hordes of undead, Minotaurs and beholders. I've personally never seen gelatinous cubes brought to life quite this well.

The game has not yet been released, but the preview seems pretty darn solid. That's increasingly rare in these woeful days of 'retail betas'. I, for one, will be keeping an eye on this game. Whether you're an RTS fan or an RPG fan or a Dungeons & Dragons fan, (and especially if, like me, you're all of the above) you'll want to do the same.