Well tower defense was indeed further defined and expanded in warcraft 3 where it saw its biggest market, and this just further supports modding of games. DOTA

Well tower defense was indeed further defined and expanded in warcraft 3 where it saw its biggest market, and this just further supports modding of games. DOTA however is from wc3 and it is especially amazing that there have been two independent games made from it, as well as many other interesting game types.