Quan Chi is a very great character. He is mysterious and evil because even though he's one of the major villians, he keeps his cool throughout the games. It's as if everything goes according to plan. He is like the Jack Sparrow of Mortal Kombat, except he's very evil.
I love his MKDA-MK (2011) attire. The single spike strap, pants and shirtless torso make him a very menacing figure. You can tell he is very powerful not only because of his muscles, but because he never seems to burst with rage. He's only ever angry in battle, which makes him a very secretive and cunning character.
Finally: his role in the MK storyline. The deadly alliance, Armageddon alliance and Shang Tsung's right-hand man in MK2011 was just awesome. I also liked how he played sort of the protagonist role in MK vs DC where he knew that the realms were endangered and advised everyone to band together to face against the new threat. It was pretty clever how he tricked Shinnok into believing he had the real amulet, when in fact Quan Chi had it all along. This makes Quan Chi seem like he is in control all the time (Except for when Scorpion realizes that it was Quan Chi and not Sub-Zero who killed the Shirai-ryu). Even when Shang Tsung betrayed him in the intro of MKD, he prevailed over him with kombat skills alone.
Quan Chi, you are a formidable foe.
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