As the leader of and longtime member of the X-Men, Storm has taken a vow to never take a life again, although she has come close on a few occasions.
The X-Men have a complicated relationship with morality, with many of their members doing questionable things over the years. Notably, many members of the team have expressed a willingness to kill if the situation becomes bad enough. One notable leader of the team tried to take a vow against it, but the situations she ends up in oftentimes forces her hand.
Why does Storm hate killing — and how often has she been forced to break her vow against it?
Throughout her earliest appearances, Storm’s morality was noble — with the hero hinting that she’d once been forced to take a life and wished to never do so again. The truth was revealed in Uncanny X-Men #267 by Chris Claremont, Jim Lee, Whilce Portacio, Scott Williams, Glynis Oliver, and Tom Orzechowski, when a de-aged and amnesiac Storm traveled with Gambit and revealed a distinct memory of traveling along the highways of Egypt as a teenager. A man offered her a ride in his truck. The naive Ororo took the ride — only for him to advance on her in an attempt to assault her. Drawing her knife and begging him not to, Ororo was forced to plunge her knife into the man’s chest to save herself. Ororo accepted the need to protect herself, but vowed to never take another life.
She carried these ideals with her when she joined the X-Men. Like the rest of the team, she was taken aback by Wolverine’s cavalier attitude towards murder, especially when it came to their enemies. Storm did her best to hold back her full power and skill, hoping to avoid taking another life. But her time with the X-Men often forced her into impossible situations that required her to reach that line — and make her angry enough to go through with it, such as when Emma Frost stole Storm’s body in Claremont and Bob McLeod’s Uncanny X-Men #151-152.
This was all done so the villain could infiltrate the X-Men and destroying them from the inside. In the process, Ororo’s mind was trapped within Emma’s body. Storm was able to adjust and — working with Kitty Pryde — was able to take back her own body. Storm saved Emma from dying in a fall immediately, only for the telepath to attack her again. Enraged by this, Storm almost lashed out and killed Emma Frost — only for Wolverine to intervene, ensuring that Storm kept from breaking her vow.
While in space during the Brood Saga, Storm was forced to use lightning against their attackers. But the blast was wilder than she expected, and it destroyed their ship — killing all the Brood aboard. A shaken Storm soon realized that she had a Brood embryo within her, threatening to transform her into one of the creatures. Storm decided to end the threat of the Brood and relieve herself of guilt by jettisoning herself into the cold blackness of space. The act killed the Brood within her, but Storm herself was saved by one of the Acanti, speaking to her guilt in taking a life and her increasing willingness to do so.