Stature

Born with a congenital heart condition, Cassie's father became Ant-Man in order to save her. He at first stole the costume, but later was given permission to wear it. Her father would team-up with the Avengers and Iron Man on several occasions through the years. After Cassie's parents divorced, her mother and new stepfather felt that it was too dangerous for her to be around her father and got full custody of her. Visiting her father one weekend a month, she stole Pym Particles in hopes of becoming like him. Cassie even lived with the Fantastic Four for a brief period, while her father was working for them as Tech support during Reed Richards absence. When her father was killed as an Avenger by a deranged Scarlet Witch, she withdrew from her mother and stepfather and planned on running away to California to join the Runaways until she saw the Young Avengers on TV. In her attempt to join them Cassie met Kate Bishop , who joined her in trying to locate them. Cassie's powers first manifested during a fight with Patriot when she tried to get her father's belongings from the Avengers Mansion. Her ability to change size seems to be linked to her emotional state, as anger has caused her to grow and guilt to shrink.

During the Civil War, she teamed up with the Runaways to free their friends and shut down an evil S.H.I.E.L.D. base. Halfway through the war, she switched sides and helped Iron Man win the war, registering under the SHRA and joining the Initiative recruits at Camp Hammond. Recently, she was kidnapped by the Puppet Master along with Arana, Dusk, and Silverclaw, but was freed from his control by Ms. Marvel and returned back to the United States. Since then, Cassie has been staying at the Initiative Training Center at Camp Hammond, working alongside the other recruits there, even aiding them against the assault of the insane clone KIA. As during this period, she came into contact with Eric O'Grady, the current Ant-Man, facing off against the "hero" in a giant-sized duel when he insulted her father. Stature was one of the over sixty superhumans at Camp Hammond to confront the insane clone KIA during his rampage throughout the base with the Tactigon, and like the others, was swiftly defeated by the alien superweapon.

Cassie survived, however, and shortly thereafter was met by the current Vision, who had just completed a worldwide sojourn to discover his true identity. Meeting him in a restaurant outside of Camp Hammond, Stature lambasted the synthetic for assuming that the Initiative forces (herself included) were either dupes for the government or villains hoping to crush America's civil liberties, defending her decision to side with Iron Man as one of responsibility and honesty, going so far to suggest that the anti-Registration forces were rebelling just for the sake of rebellion or out of some romantic revolutionary ideal rather than out of an educated decision. The pair were ambushed by AIM terrorists shortly thereafter, and upon defeating them, Cassie was stunned when the Vision declared his love for her. Although intrigued by the gesture, she decided to take some time to sort out her feelings for him instead of accepting him outright. Cassie was then faced with an almost tragedy. During a fight with the Growing Man her stepfather Blake was seriously injured. The guilt caused Cassie to shrink to almost nothingness. But with help from her friends Wiccan, Hawkeye and Patriot she was able to snap out of it before she shrank to nothingness. She later saw Blake in hospital and he forgave her.

During the Secret Invasion Cassie first fought the Skrulls during their invasion of New York. She was quickly defeated but survived the conflict. She later took part in final battle and she was able to grow larger then the Skrull Yellowjacket and take him out with a single punch.

She is a member of both the Young Avengers and the Mighty Avengers along with her love interest Jonas (Vision 2.0).

Dark Reign

Vision and Stature are on the ruins of the Avengers statue memory lane. There a new statue appeared showing the death of Wasp. Suprisingly they see statues of the Young Avengers there too they notice that they have been cover in some kind of goo making super heroes into statues. They flee from this and see the unexpected, the woman who the original Vision loved and who killed Cassie Lang's father, the Scarlet Witch, but before any of the three can say anything Wanda teleports them out of trouble. Stature later helps the rest of the future Mighty Avengers in saving the world from Chthon's chaos.

Later by the words AVENGERS ASSEMBLE spoken by Hank Pym, now Wasp, and the help of the Scarlet Witch's powers the new Mighty Avengers are summoned: The Wasp, Jocasta, Vision, Stature, Amadeus Cho, Hercules,  Jarvis, and U.S. Agent. .

It has been revealed that Cassie is still doubting her place in the Mighty Avengers. She feels strong ties and obligations to the Young Avengers, and she continually expresses a desire to return to them, at the very least so she can inform them of what she and Jonas had been doing. She also shows a strong desire to maintain her father's legacy and good name, complimenting Cho on using the old Ant-Man helmet (since he's someone she actually likes), and being reluctant to lay siege to the Baxter Building since her father was once a member of the Fantastic Four. 
 
Cassie brings the Young Avengers to the Mighty headquarters to confront the Scarlet Witch, but to their surprise they find out that Scarlet is Loki in disguise.

Powers and Abilities:

A baseline human originally, Cassie deliberately exposed herself to concentrated Pym Particles during her visits to Avengers Mansion, hoping to replace the powers of her father, the second Ant-Man. The attempt was successful, granting Stature the ability to grow and shrink, altering her strength and stamina in relative proportions to the transformations. While the upper and lower limits of this ability have yet to be determined, it has been demonstrated that Cassie can grow to a size of at least thirty feet tall, and shrink down to the level of an ant. Due to repeated exposure to the Pym Particles, Cassie's physiology has absorbed enough to let her change size at will. Moreoever, emotional changes have also caused transformations, as her body subconsciously reacts to mood swings or changes in temperament, Anger causes Cassie to grow and guilt causes her to shrink. Cassie's abilities seemed to be increasing since she has shrunk to microscopic size and grown taller then most buildings. This is roughly a limit of 250 feet. Also she seems to be able to change the size of the clothes she wears.

Alternate Realities

Earth.982

In the MC2 reality Cassandra is known as Stinger.

In another reality Cassie found herself in Wonderland and meeting many alternate versions of the Young Avengers. At first her emotions cause her to grow and shrink beyond her control. She also meets an alternate version of Ant-Man (Scott Lang) and Tigra. Cassie grows up a little while she is Wonderland after being put on trial by the King and Queen.

In What If: Civil War Cassie is reportedly killed when by sentinels.