Strategy game, top-down view, medieval setting.

[royozin]

You have one map where you can only walk on various squares, and the rest of the squares are pitch black, like in space.

You can spawn these blue units at your spawn points that look like humans when they walk but turn into obelisks/pyramids when they stop moving. You can also place them on these squares to combine them into a special unit. It's pretty slow paced, and there is also some smaller unit that can walk on walls.

[Scatty]

Blood & Magic (http://www.mobygames.com/game/dos/blood-magic)

A really awesome but pretty much forgotten game from Tachyon Studios and Interplay, with both out of the scene today. Due to the success of Warcraft II and Age of Empires during that time it went unnoticed.
That smaller unit is probably the gnome who can walk on walls and buildings which gives bonus to his defense.