The answer is simple really. You have to find his weak spot. To understand Crota you have to examine the beast and understand it's background. As a child, Crota grew up with an abusive mother and his father was never around. This lead to Crota to a troublesome childhood filled with street violence, gangs, and even drug use. Crota was a high school dropout, but soon formed a small group known as the "HIV". This form of misspelling led to many taunts by local gangs, thus lowering any real street cred the gand may have had. It wasn't until Crota met a young hoodrat named Omnigul that the gang truly would rise to the top. Now with the gang on the rise to the top, Omnigul stepped in and correctively changed the name of the gang to the "Hive." Omnigul was educated. You hear that kids!? Stay in school and you won't be no fool. What's the point to all this back story you ask? Well it's quite simple really. Crota is an asshole and his weak spot lies deep within his anal glands. Crota also has a weakness for Justin Bieber songs and Ryan Gosling movies. You could either give the creature a prostate exam or turn on "The Notebook" and wait for the savage beast to be in tears to take him out. I wouldn't suggest putting on Justin Bieber music, because it may lead to your own suicide.