Blood Elf Engineer

Blood Elf Engineers are blood elf units, produced at the Town Hall or Castle, who build Energy Towers, Boulder Towers, Flame Towers, Cold Towers, and Death Towers. They appeared in the Warcraft III: The Frozen Throne Alliance campaign to aid Kael'thas in a secret level, so the extent to which they are canonical is debatable. According to them, they helped construct the defenses of Dalaran. They are more expert variants of the blood elf workers.

Statistics from Warcraft III

 * Builds Energy Towers, Boulder Towers, Flame Towers, Cold Towers, and Death Towers