Researchers studied how a fungus called Arthrobotrys flagrans catches and kills parasitic worms. They found that three genes containing a special protein domain called CFEM control how the fungus produces sticky traps and deadly proteins. By studying mutant fungi with these genes deleted or overexpressed, they discovered that these genes work together and can compensate for each other, helping explain how this fungus could be used as a natural pest control for harmful nematodes.