Jax is one of the most notable characters in the world of "Mortal Kombat." Since his debut, Jax has become one of the most popular Mortal Kombat characters ever. On another note, Jax is perhaps the token black person in the Mortal Kombat series. Ever since debuting in "Mortal Kombat 2," Jax has become one of the most popular characters ever.
In his storyline, Jax is short for Jackson Briggs. He is the direct superior of Sonya Blade from the first Mortal Kombat game. At the end of the first Mortal Kombat game, it is revealed that Sonya chased Kano into Outworld. However, Sonya and Kano were captured by the forces of Shao Kahn who rules the realm of Outworld. During that time, Jax had no idea what had transpired in the first place. That was not until actor Johnny Cage appeared outside of HQ. Jax interrogated Cage about what happened.
At first, Jax did not believe Cage. But, he believed Cage's story after geting a transmission from Sonya. Then, Jax and Cage would join forces when Cage got attacked during a commercial shoot.
Then, Jax would go into Outworld to rescue Sonya. Successful, they left Earthrealm. However, Kano eluded arrest again. This would lead into the events of "Mortal Kombat 3" where Jax learned about Shao Kahn's plans of taking over Earthrealm. Unfortunately, the superiors did not buy Jax's story.
Jax, preparing for war, outfitted his arms with bionic implants. He would become one of the few surviving Earthrealm warriors to fight against the forces of Outworld and rescue Earthrealm. As a result, the Outerworld Investigation Agency (OIA) was formed with Jax as the commanding officer. Instead of sorcery, the OIA would use science to open portals into other realms.
In the events of "Mortal Kombat 4," he and Sonya would track down Jarek who is the last surviving member of the Black Dragon. During that time, they would align with Jarek to protect Earthrealm and Edenia from the fallen Elder God known as Shinnok. Also, they freed Cyrax from his robotic programming. This would make Cyrax the fourth black person in the Mortal Kombat series. Kai and Tanya are the second and third black people in Mortal Kombat. Those two were introduced in Mortal Kombat 4.
Jax would take action again in "Mortal Kombat: Deadly Alliance." This is due to a member named Hsu Hao being a mole for the Red Dragon syndicate. Hsu Hao ended up nuking the OIA headquarters under orders of the Red Dragon leader, Mavado. Jax would join Raiden in fighting the Deadly Alliance of Shang Tsung and Quan Chi. But, Jax would have his own ulterior motives.
In this respect, both the Black Dragon and Red Dragon syndicates have a beef with Jax. Kano has to wear the metal place with infrared eye due to Jax. Jax tossed Jarek over a cliff. And Jax ended up tearing out Hsu Hao's artificial heart.
But, Jax was seemingly killed by the forces led by the Deadly Alliance. He would be resurrected by and brought under the control of Onaga who is the main antagonist of "Mortal Kombat: Deception." On that note, Jax is a secret character that can be unlocked when you finish some certain modes.
Jax returns for "Mortal Kombat Armageddon" siding with the forces of light. It seems that Jax has somewhat of a sub-plot with Sektor.
Jax is also a playable character in "DC Universe vs. Mortal Kombat" in which his DC Comics rival is Lex Luthor.
Jax is also present in the live action film called "Mortal Kombat: Annihilation" played by Lynn Red Williams. In the revisioning proposal, called "Mortal Kombat Rebirth," he is portrayed by Michael Jai White.
Overall, Jax is a very impressive character for the most part. His sets of moves let alone Fatalities have changed with each title. In Mortal Kombat: Deadly Alliance, you can spam Jax's machine gun move. One could say, Jax is one of the best characters in the game. It seems highly likely that Jax will return for more future titles.