Towers were buildings in Warcraft: Orcs & Humans.
Towers are the mystic places where magiks are taught. These strange and mysterious workers of magic are a reclusive lot, and place themselves above the law in many ways. They also demand absolute secrecy and privacy for their studies, and so require their own domicile. Conjurers gather at the Tower to practice and train in their arcane arts. When new magiks are learned, that knowledge is immediately sent by thought to other conjurers wherever they be in the realm. The recruiting of Conjurers is a common practice, but a price must be paid in gold for their services, as few hold duty to anyone. The massive energies used in their spells require that the Tower be constructed with long shafts of metal placed within the stone walls to act as a mystic lightning rod, for without these, the building would explode into a thousand pieces. A blacksmith must be made available to create these devices to the exact specifications provided by the Conjurers.
This is where the knowledge of the dark magiks are revealed. Warlocks reside here to focus their energies towards harnessing the forces of the underworld. Their sect demands payment in precious metals for any services they may offer, as it is then converted into the mystic symbols used in their castings. Metal cages in which to place the subjects of their experiments must be constructed, as well as the ornate metal runes that need to be built into the stone floors for their spells of summoning. Only the blacksmith can provide the needed materials and skills required to meet these exacting specifications.