Complex sentence: The "Dota" franchise, which includes the "Warcraft III" mod "Defense of the Ancients" and its stand-alone sequel "Dota 2" are amongst the most popular electronic sports games played professionally.
Split into simpler sentences: The "Dota" franchise began as a Warcraft III mod named "Defense of the Ancients". Together, the games are amongst the most popular electronic sports games played professionally.