The Masked Guards are a group of (most likely Outworlder) royal protectors to Shang Tsung and later to Shao Kahn. They appeared in the background for Mortal Kombat, Mortal Kombat Trilogy, Mortal Kombat: Deception, and are more prominently featured in Mortal Kombat: Shaolin Monks. They also make an appearance in Mortal Kombat (2011).
In Shaolin Monks, they have the ability to block almost all of the player's attacks, causing the player to rethink how to fight them. The Masked Guards fight with a bladed staff-like weapon (the naginata), and use a katana as a secondary means of assault. Also, a single Masked Guard appeared in the opening of the Mortal Kombat II, and a dead Masked Guard is seen in the opening shot of the Mortal Kombat: Armageddon and Mortal Kombat 11 introduction video. John Vogel played the Masked Guards seen in the original Mortal Kombat arcade game.
In Mortal Kombat (2011) and Mortal Kombat: Shaolin Monks, Kung Lao disguises himself as a Masked Guard to gain access to the Mortal Kombat tournament. The Masked Guards can also be seen around the Courtyard.
The Masked Guards make an appearance in the first Mortal Kombat movie as ninjas loyal to the sorcerer Shang Tsung, one of which is pitted against the Elder Sub-Zero by Tsung in a pre-tournament match and is killed in the process.
They also do battle with the three chosen heroes of Earthrealm by Raiden and the Shaolin Monks, Liu Kang, Johnny Cage and Sonya Blade after they are discovered spying on Tsung, Goro, and Kano, but are defeated. More arrived, but were backed off by Raiden (which Johnny gloats to the guards that they got lucky).