To unlock Dong Zhuo as a playable warlord in Total War: Three Kingdoms
By playing through a campaign and expanding your prestige until you are declared one of the Three Emperors, the game will automatically unlock Dong Zhuo for future playthroughs. This method takes longer in terms of turn count but happens naturally as you progress toward winning the game with any faction. Why Play as Dong Zhuo? total war three kingdoms unlock dong zhuo
You don't necessarily have to kill him personally in a duel, but you must win a battle where he is the commanding general. To unlock Dong Zhuo as a playable warlord
Move your armies toward his territory. You may need to pass through neutral territory. If you are playing a "good" faction (like Liu Bei), the other warlords will likely support your war against him. You don't necessarily have to kill him personally
There are two ways to unlock Dong Zhuo:
I can give you the exact strategy to get him into your roster quickly.