inspired by HL *Half-Life* series from VALve
reference image (https://external-content.duckduckgo.com/iu/?u=https%3A%2F%2Fupload.wikimedia.org%2Fwikipedia%2Fcommons%2F6%2F61%2FM9-pistolet.jpg&f=1&nofb=1)
