I have a mid 2014 MacBook Pro(Model A1398 EMC 2881) that after the chime on startup enters a black screen and then into a unique login screen I have never seen before. At the top right corner of the screen there is a command prompt which stops blinking when I type but no characters appear. When I select a user it will move the user icon to the center of the screen and the other disappears like usual but nothing will happen until the computer powers itself off after a bit. I am unable to enter safe mode, single user mode, or recovery mode, it goes through the same screens every time. I have tried a few PRAM resets to no avail. Sometimes it can take a minute to start, sometimes 20 minutes. Any info or advice is appreciated. Thanks in advanced.