DOTA is a series of strategy video games by Valve. The series began in 2003 with the release of Defense of the Ancients (DotA), a fan-developed multiplayer online battle arena (MOBA) mod for the video game Warcraft III: Reign of Chaos and its expansion, The Frozen Throne.
The original mod features gameplay centered around two teams of up to five players who assume control of individual characters called “heroes”, which must coordinate to destroy the enemy’s central base structure called an “Ancient”, to win the game.