Blood & Magic is a computer game released by Interplay in 1996. It was the second real-time strategy game to use the Dungeons & Dragons license.
The basic units of the game are the Basal Golems, which are created at the Bloodforge. They provide mana for the production of new units and can be turned into buildings or monsters. When four are placed on a foundation, they may transform into a mystical site dedicated to the kind of magic the player’s choosing. Placing a Basal Golem adjacent to a friendly mystical site will allow them to change into a different creature, based on the type of mystical site. The player automatically is only able to use the weakest transformation, and can unlock more by researching. Researching costs experience, which is gained by creating or transforming Basal Golems, creating or destroying structures, casting spells and slaying enemies.
The single player game consists of five regular campaigns of increasing difficulty followed by a world conquest (a long campaign during which the player conquers all 15 maps and then challenges the gods themselves). In all regular campaigns the player can choose one of two sides of conflict. To unlock the next campaign, the player has to finish the current campaign at least once. The storylines of all campaigns are typical fantasy tales (without any explicit AD&D references), although each campaign has its own take on the genre. The stories are told between battles by a narrator voice (often in verse) and illustrated by gradually uncovered pictures.
Source: Wikipedia, http://en.wikipedia.org/wiki/Blood_and_Magic, available under the CC-BY-SA License.