Almost similiar to a scenario in the Night Elf Campaign of Warcraft III: Reign of Chaos. This is the last scenario of the campaign and you need to survive for 45 minutes. The archimonde is Gargerensis and there is an extra 30 seconds to survive, you can know the full story by watching out for the dialogs. Require quite a powerful computer to prevent lags during the battles. I recommend playing at Hard level. I almost failed the mission myself at Titan level. Have fun!