This is significant because Mor Havoc is in the units list in the Editor but not in any official scenarios.
Dawn of Civilization was replaced by the Ascent of Egypt Learning Campaign in the final builds of the original Age of Empires, and is only present in select known alpha/beta builds, such as the one bundled with Computer Gaming World (CGW) Magazine. https://ageofempires.fandom.com/wiki/Dawn_of_Civilization
The description in the Granary says: "Demo Version of AoE exclusive to CGW (Computer Gaming World) Magazine, from Issue #160 CD-ROM, November 1997. Build is late Beta, and 5-scenario campaign is exclusive to CGW."