I need a partner to get this achievement to make it easier. We can do the mission 2x so that we both get the achievement. The first time one person goes through killing grunts while the other sits back and wait until they’re dead. And then we do the mission again so that the other person can get the achievement. It will be easy because we can use the grunt funeral skull and the bandana and boom skulls. Message me if interested on Xbox Live.
GT - Loomer xx