Marines attending the Methods of Entry School, a course that is considered high-risk by Headquarters Marine Corps, conduct an emergency drill at night on Dec. 18. The drill involved a simulated breaching operation gone wrong, with resultant simulated injuries. - Marines attending the Methods of Entry School, a course that is considered high-risk by Headquarters Marine Corps, conduct an emergency drill at night on Dec. 18. The drill involved a simulated breaching operation gone wrong, with resultant simulated injuries.