Sindel/Current Timeline

"We are bonded in death. You will join us...and I will give you a proper upbringing!"

- Sindel to Cassie Cage in Mortal Kombat X.

Biography

 * Mortal Kombat (2011): "The mother of Kitana, Queen Sindel was forced into marriage with Shao Kahn when he conquered her realm of Edenia. In an attempt to thwart the emperor's designs on Earthrealm, she sacrificed herself. Her suicide created a magical ward preventing him from setting foot there. But now the barrier has been dissolved. Sindel has been resurrected, her mind enslaved by Shao Kahn. Earthrealm's former ally has become a deadly threat."

Mortal Kombat
Sindel is resurrected by Quan Chi, who was accompanied by Noob Saibot. While Sindel's suicide provided protection for Earthrealm, her resurrection causes the protection to dissipate, allowing Shao Kahn to proceed with new plans. After Motaro is killed by Raiden, Shao Kahn takes the souls from Shang Tsung's body (killing him in the process) and grants his queen/empress the power needed to defeat her enemies.

With the new powers of Shang Tsung's souls, Sindel leads the Lin Kuei cyborgs, along with Cyrax and Sektor, in an attack on the Earthrealm warriors. While the cyborgs are all defeated, Sindel attacks and kills almost all of the Earthrealm warriors, and fatally wounds her own daughter, Kitana. She then ignores her daughter's pleas before draining her soul. She is then challenged by Nightwolf, with the latter emerging victorious. Yet the shaman is forced to sacrifice himself to destroy the Outworld empress. Only Johnny Cage and Sonya Blade survive, but with major injuries. When Raiden and Liu Kang return from their visit with the Elder Gods, they find a dying Kitana. Kitana eventually dies from her wounds inflicted by Sindel while talking with Kang.

In an attempt at stopping Shao Kahn, Raiden goes to the Netherrealm to plead for Quan Chi's assistance. The necromancer states that he already has all of the souls from the recent battles, which includes Sindel's soul.

Mortal Kombat X Comic Series
Sindel is seen briefly as Sub-Zero recalls his death at her hands.

Mortal Kombat X
As a corrupted revenant, Sindel participated in Shinnok's invasion of Earthrealm, and was one of the key figures in the assault on Raiden's Sky Temple. Just outside the Jinsei Chamber, Sindel attempted to kill Fujin with her Migraine fatality, only to be intercepted and defeated by Raiden.

25 years later, she does battle with the former revenant Jax in the Netherrealm, where she is defeated. Any chance Raiden has at restoring Sindel and the other revenant heroes to an uncorrupted form is lost when Quan Chi is killed by Scorpion.

After Shinnok begins corrupting the Jinsei, Sindel confronts Cassie Cage. Cassie asks whether she feels guilt for killing her own daughter Kitana, and Sindel replies that they have been reunited in death as a real family. She offers to give an undead Cassie a proper upbringing as well, but is refused and defeated.

When Cassie goes to confront Shinnok, Sindel helps the other revenants battle Cassie's allies. After Shinnok is defeated, she and her cohorts make haste and disappear back to the Netherrealm. She likely continues to serve Kitana and Liu Kang, the new rulers of the Netherrealm.

Ending

 * Mortal Kombat (2011) (Non-Canonical): "The spell that bewitched Queen Sindel had been broken. She did battle with Shao Kahn and slew him—punishment for the suffering he brought upon her and millions of others throughout the realms. She dissolved the sorcery that bound Edenia with Outworld and began restoring her realm to its former glory. The many races of Outworld were impressed. Not only had Sindel defeated Shao Kahn, but she had shown great leadership in chaotic times. They willingly offered her their allegiance. Under Sindel’s governance, the realms of Edenia and Outworld remain merged in spirit."