"Career Killer" can refer to several things depending on the context. Please see the relevant article for what you are looking for.
If you're looking for a character who has made a career out of killing people, see:
If you're looking for something that can kill your career, we have multiple tropes for that:
For writers, artists, producers, etc., a "Career Killer" is a work that ends up being more harmful than helpful to their careers:
- Creator Killer: a work which threatens the viability or harms the reputation of its writer(s) or producer(s).
- Franchise Killer: a work within a long - running franchise that destroys hopes for further sequels.
- Genre-Killer: a work that results in an entire subgenre falling out of fashion.
- Ink-Stain Adaptation: a work within a long - running franchise that colors the public perception of the franchise as a whole.
- Star-Derailing Role: a work that damages the reputation of performers taking part in it. It may be a result of Contractual Purity.
Taking a new job can also destroy a career:
- George Jetson Job Security: a job that comes with a boss who likes to fire people for the most minor mistake.
- Kicked Upstairs: a character is deliberately promoted to a high - ranking but unimportant role, in order to remove them from their current, more important role.
- Promoted to Scapegoat: a character is deliberately promoted to a seemingly important role, in order to use them as The Scapegoat.
- Reassigned to Antarctica: a reassignment to a remote location intended as a punishment or to simply get rid of a character.
For other things that destroy characters' careers in-universe, you might be interested in:
Of course, there are also career moves that can get someone killed:
- Retirony: A Mauve Shirt who has held a dangerous job for many years dies within days of their retirement date.
- Uriah Gambit: a character is deliberately given a particularly dangerous reassignment in hopes they won't come back.