 The Dota series began in 2003 with Defense of the Ancients ( DotA ) — a mod for Blizzard Entertainment 's Warcraft III : Reign of Chaos — created by the <unk> designer " <unk> " . An expansion pack for Warcraft III , entitled The Frozen Throne , was released later that year ; and a series of Defense of the Ancients clone <unk> for the new game competed for popularity . DotA : Allstars by Steve Feak was the most successful , and Feak , with his friend Steve Mescon , created the official Defense of the Ancients community website and the holding company DotA @-@ Allstars , LLC . When Feak retired from DotA : Allstars in 2005 , a friend , under the pseudonym " IceFrog " , became its lead designer . The popularity of Defense of the Ancients increased significantly : it became one of the most popular <unk> in the world , and , by 2008 , a prominent eSports title . IceFrog and Mescon later had a falling out in May 2009 , which prompted the former to establish a new community website at <unk> 
