- "I'm the daughter of Vandal Savage, the immortal ruler of the world."
- —Cassandra on herself to Leonard Snart[src]
Cassandra "Cassie" Savage is the daughter of the late Vandal Savage and a late unnamed woman. She was a loyal lieutenant of her father's, believing in his goal for world domination to be a noble quest to unite the world. However, after learning that he himself released the Armageddon virus that flung the world into chaos and killed her mother, she turned on him and chose to aid the resistance.
Cassandra stood by her father's side as he gave a speech to his soldiers, and noticed Rip Hunter, Sara, Snart, and Mick in the crowd. When the members of Rip Hunter's team attacked after the speech, Cassandra fought Sara, during which Kendra noticed Cassandra was wearing the bracelet she wore on the day she died back in Egypt, telling Sara to grab it. However, more forces arrived, forcing them to retreat.
Later, Snart and Mick attempted to steal the bracelet from her, but wound up having to kidnap her, only discovering once back on board the Waverider that she was Savage's daughter. After the team debated what to do with her, Snart went to talk with her, discussing their fathers. Cassandra expressed her belief that her father was trying to save the world from Per Degaton's Armageddon virus, the same virus that killed her mother. She dared him to torture her, but he left.
After Vandal attacked with the Leviathan, Snart released Cassandra, showing her innocent refugees they had rescued. She remained unconvinced of her father's villainy, until Snart had Gideon run footage of her father suggesting the release of the Armageddon virus. She returned to her father, causing him to be overjoyed. However, he noticed that her bracelet was gone (having been utilized by the team), leading him to realize her treachery. The rest of the team confronted Savage, but his guards arrived, forcing all, including Cassandra, to flee. Snart took Cassandra to a rebel base outside of the city, where she offered her assistance.
Personally raised and trained by her father Cassandra was a soldier who believed her father was doing the right things. Tricked into thinking that Per Degaton was the one who had unleashed the Armageddon virus which had killed her mother and countless others, once her father had killed Per Degaton and began a campaign united the entire world under his command, she believed that any violence he used was necessary as the rebels were wrong for going against her father. 
Despite her strong allegiance to Vandal, deep down she had doubts about his actions. It wasn't until Leonard Snart showed her that it was her father in fact who had unleashed the virus and was killing innocents to gain power she changed her mind and joined the team in taking down her father. Rejecting everything Vandal ever taught her, she denounced the immortal tyrant as her father.
- Expert swordswoman: Cassandra is a highly skilled swordswoman. She was able to hold her own against Sara Lance, though Sara did seem to have the edge. She was shown easily subduing multiple swordsmen during a sparring match.
- Expert hand-to-hand combatant: Cassandra is trained by Vandal Savage in close combat, being able to defend herself against highly skilled fighters like Sara Lance.
- Skilled tactician: Personally trained by her father Vandal in the arts of warfare and subterfuge. She became a high ranked member of his regime and knows all of the tactics and methods of his army. She also was trained at deception but was unable to avoid her father seeing through her lies.
- Skilled knife-fighter/knife-thrower: Cassandra can throw knives with precision. Throwing a knife at Mick Rory (which he dodged) and killing a guard by throwing a knife in his back.
- Indomitable will/Tolerance for pain: Cassandra is trained by Vandal to withstand all kinds of torture.
DC's Legends of Tomorrow
Behind the scenes
- In the DC comics, Vandal Savage has two (known) daughters, one named Scandal Savage, the other named Kassidy Savage.