Nemeses

Her lack of self-control when it came to spending was her financial nemeses.

The computer virus was the nemeses of the company's entire network.

The hiker's nemeses, blisters on her feet, made it difficult for her to continue on the trail.

The nemeses of computer hackers are the cybersecurity experts who work to keep their networks safe.

The detective and his nemeses engaged in a cat-and-mouse game that lasted for years.

The nemeses of the detective were always trying to outsmart him.

The hiker's nemeses were the difficult terrain and bad weather.