i thought this would be a good idea, y'know a Garry's Mall ported in Left 4 dead's workshop as a survival map, sprinkle in a bit fortifications with turrets, place all weapons & items in the mall.
it be cool

here's the link if you wanna take a look ( you must own Garry's Mod, other requirements will be in the links description in order to see Garry's Mall in its full potential )
credits to the map creators in Garry's Mod Workshop

https://psteamcommunity.yuanyoumao.com/sharedfiles/filedetails/?id=207060996&searchtext=garrys+mall