Zombie

A zombie is a reanimated corpse, brought back to life by magic.

History
Liu Kang was an infamous example of a zombie in the MK series. Raiden, who was corrupted by his suicide, had used necromancy to reanimate Liu Kang's body as an enforcer of the dark thunder god's will. Raiden had then unleashed Liu Kang's active corpse to destroy those who Raiden believes have caused harm to Earthrealm.

In Mortal Kombat: Deception's Konquest mode, zombies are shown to endlessly roam the wastelands of the Netherrealm. They were identified by an Oni Guard as beings that are "punished to roam the wastelands as reanimated dead".

Other zombies scene in the series would be the "undead" clan of Scorpion. The Elder Gods had promised to resurrect Scorpion's clan in exchange for his service to them as their champion. Unfortunately for Scorpion, the Elder Gods did not fully fulfill their promise as they had brought back the Shirai Ryu as animated dead. Infuriated, Scorpion vowed revenge against the Elder Gods. Scorpion attempted his revenge by sending his undead clan to kill Taven in order to ruin the Elder God's plans to save the realms from Armageddon. However, Taven was able to defeat the undead Shirai Ryu.

Trivia

 * Zombies could also be created in the Kreate-A-Fighter mode of Mortal Kombat: Armageddon.