Age of Empires II: The Age of Kings Promo Art (Windows)
Available in the screenshot section on the official website (October 1999)
Press High Resolution Art (2000)
Images originally published as part of E3 '98 coverage at: http://www.cdmag.com/articles/012/019/aoe2_news.html (page archived by the Wayback Machine).
In April 2000 the UK magazine PC Strategy Games included a demo