Well you pretty much have it covered, But I can't recall myself, I know Shinnok threatened Earth but did he actually try to sieze it? And all Earth's warriors were in the Netherealm, I assume thats where Shinnok was based while taking over Edenia.
Thousands of years ago in a battle with the fallen elder god known as Shinnok, I was responsible for the death of an entire civilization. To rid all realms of Shinnok's menace I waged a war that plunged the earth into centuries of darkness and banished Shinnok to a place called the Netherealm. Now after Shao Kahn's defeat at the hands of the earth warriors, Shinnok has managed to escape his confines of the Netherealm. The war is now being fought once again, and this time it can be won by mortals.
- The Words of Raiden
Maybe these bios will help you get the gist of MK4. (Have you ever played it?) MkGold is far better.
Shinnok
Banished to the Netherealm for crimes committed against his once fellow Elder Gods, Shinnok is freed from his confines by Quan Chi. With the aid of a traitor he is then able to take the Realm of Edenia. From there he wages a war against the Elder Gods, and awaits a chance to enact revenge against the God who banished him there - Raiden.
Kai
A former member of the White Lotus Society, Kai learned his skills from the great masters throughout Asia. He journeyed to the Far East after meeting his friend and ally, Liu Kang in America. Now, they reunite to assist Raiden in the battle with Shinnok
Raiden
The God of Thunder returns to Earth after the defeat of Shao Khan - but finds anew threat when Shinnok's forces, led by Quan Chi attack the Elder Gods. With the heavens in disarray Raiden exists as one of the last Gods of Earth. He must come to the aid of his elders and put an end to his evil villainous reign of his ancient enemy.
Liu Kang
Still the immortal champion of Mortal Kombat, Liu Kang finds himself venturing into the realm of Edenia to rescue the princess Kitana from the vile clutches of Quan Chi. Unsuccessful in his mission Liu returns to Earth and mounts an effort to bring together Earth's greatest warriors. He does it this time not only to free Kitana's home world but also to assist his mentor and Earth's protector - Raiden.
Reptile
A general in Shinnok's Army of Darkness, Reptile once belonged to an extinct race of reptilian creatures. He was banished to the Netherealm for committing genocide against several species. Responsible for the death of millions, Reptile is a dangerous ally to the forces of evil.
Scorpion
In hopes of gaining Scorpion as a new ally in the war with the Elder Gods, QuanChi make the dead Ninja an offer he cannot refuse - Life, in exchange for his services as a warrior against the Elders. Scorpion accepts, but hides under alterior motives.
Jax
When Sonya disappears while tracking the last living member of the Black Dragon, Major Jackson Briggs heads after her. He soon finds that Sonya's mission has led her into a battle with the forces of an evil Elder God. This is a battle they must win or their own world will crumble at the hands of Shinnok.
Reiko
Once a general in Shinnok's armies, Reiko lead the forces of darkness into the battle against the Elder Gods. Once thought killed during that onslaught, he resurfaces and joins the battle against Earth's forces.
Johnny Cage
After Shao Kahn's defeat, Cage's soul is free to leave to a higher place. From the heavens, he observes his friends engaged in battle. With the heavens in disarray, he learns of the war waged against the Elder Gods by Shinnok. Cage seeks out Raiden to help him restore his deceased soul and join Liu Kang in his quest. Once again, Johnny Cage finds himself fighting alongside Earths greatest warriors.
Jarek
Believed to be the last member of Kano's klan, the Black Dragon. Jarek is hunted down by Special Forces agent Sonya Blade for crimes against humanity. With the emergence of a much greater evil, Sonya focuses her strengths on the new menacing Quan Chi. Jarek now finds himself fighting alongside Sonya and Earth's warriors to help defeat the Evil Elder God, Shinnok.
Tanya
As the daughter of Edenia's ambassador to new realms, Tanya invites a group of refugees fleeing their own world into the safety of Edenia. But soon after Queen Sindel allows them through the portal, she learns that one of the warriors is none other than the banished Elder God, Shinnok. The opened portal leads not into another world but into the pits of the Netherealm itself. The once free realm of Edenia is now at the mercy of Shinnok.
Fujin
Better known as the God of Wind, Fujin joins Raiden as one of the last surviving Gods of Earth. Their counterparts were defeated in a war of the heavens between Shinnok's forces and the elder gods. He now prepares for the final battle between the forces of light and Shinnok's hell spawned warriors of darkness.
Sub-Zero
After Shao Khan's defeat at the hands of Earth's fighters, Sub-Zero's warriorclan known as the Lin Kuei is disbanded. But w/ the new threat brought on by Quan Chi, the ice warrior once again dons the familiar costume once worn by his brother the original Sub-Zero. He also holds secrets passed onto him from his sibling - secrets that could hold the key to stopping Shinnok.
Quan Chi
A free roaming sorcerer powerful in the black arts, Quan Chi uses his abilities to free the now evil Elder God Shinnok from his confines in the Netherealm. In exchange for his services Shinnok has granted Quan Chi the position of arch-sorcerer of his now expanded Netherealm.
Sonya
After her journey into the Outworld and Shao Khan's near destruction of earth, Sonya becomes a member of Earth's own Outworld Investigation Agency. Her first mission leads her to join Liu Kang on his quest to aid the troubled thunder God, Raiden. She must survive long enough to warn her government of the new menace brought on by Quan Chi.
Noob Saibot
Noob returns to serve under Shinnok again after aiding the Earth Warriors to overthrow Shao Khan's minion. After a thought successful extermination of Shao Khan, Noob returns again to serve as a General in Shinnok's Army of Darkness
Goro
The half human dragon stood as Shang Tsung's protector in the first tournament. Goro took the Mortal Kombat title from the original Kung Lao, only to have it won from him nine generations later by Lao's ancestor, Liu Kang. Seeking Revenge, The Shokan Prince has returned from the Outworld to crush Liu Kang in Mortal Kombat.
Cyrax
Cyrax is finally rescued from his desert prison by the Lin Kuei. The physical damage sustained while in the desert was relatively easy to repair, but Cyrax seems very different from when he first set out on his original assassination mission against Sub-Zero. Only time will tell how well Cyrax has overcome his ordeal.
Mileena
Reborn in the Netherealm and servant to Shinnok since her rebirth, Mileena finds that the coming battle gives her a chance to both escape her fearful servitude to Shinnok and avenge her own death. Knowing Kitana will fight for Edenia, Mileena ensures an easy escape route is left as she moves into battle with Shinnok.
Kitana
As Quan Chi forces leave her realm of Edenia to battle Raiden and his forces, Kitana manages to escape the remaining guards surprisingly easy. She think little of her escape and moves quickly into the battle against Shinnok and Quan Chi. Edenia's future depends on her success.
Kung Lao
Many believe that Kung Lao had died in injuries suffered during the final fight against Shao Khan. In fact he had merely turnd to a new life without violence in reverence to his ancestral beliefs. As news of Shinnok's threat reaches Kung Lao together with the apparent return of Goro, Kung Lao returns once more to challenge his ancestor's killer.
Baraka
Ever the nomad, Baraka has spent much time wandering many realms. Whilst travelling back through Edenia, he is made an offer to rule the realm at the side of Quan Chi. Eager to return into battle for any cause, Baraka accepts, but has a different idea of how things will turn out.
Sektor
Even suspicious of the effect of Cyrax's prolonged exile in the desert, the Lin Kuei are forced to send him since their forces are vastly reduced. In the guise of fighting alongside his Lin Kuei comrade, Sektor's orders are to watch and report on Cyrax. Sektor's reports will decide whether this is the last mission for Cyrax.
