Composers are unsourced and unmentioned in article
The Genie engine is unsourced and unmentioned in article
The release platform is unsourced and unmentioned in article
The artist is unsourced and unmentioned in article
The programmer is unsourced and unmentioned in article
The designer is unsourced and unmentioned in article
Gameplay
Tweaked a bit to clarify what it adds content to.
I think a section + see also to AoEVG dedicated to explaining how AoE works would be valuable, as I think that without an explanation, these details may be more difficult to understand for those who don't know what kind of game AoE is. This should also clarify that it's a real-time strategy game. As an example of the issue, I feel that the population limit is not well explained, and would be hard to explain without describing the functions of units and supply.
The sentence on the historical reenactments could be tweaked to flow a little better, maybe split into multiple sentences?
Development and release
"The expansion was conceived during a delay in the development of the game's sequel, Age of Empires II: The Age of Kings, which the studio identified needed more time beyond its planned release date of 1998" This reads a little confusing, it might be just on me though. I wasn't sure if it was a typo and it's meant to say "which the studio identified as being due to needing more time beyond..." or if it's "[Ensemble Studios] identified needing more time..." or something else.
Images
Screenshot should specify exactly what it's doing in the article, ie why specifically it is used. For example, to visualize its depiction of Ancient Rome, to show the gameplay, to show the perspective, anything about the gameplay that might be discussed by critics that could be used to justify it.
