You are guaranteed an interview for a Missouri state position once you are on the register of eligible applicants, if you are a current or former member of the Missouri National Guard.
Apply for the state position, get onto the register of eligibles, and tell the hiring agency you are a current or former Missouri National Guard member entitled to a guaranteed interview.
Proof of your current or former Missouri National Guard service, such as your NGB 22, military ID or a unit memorandum.