Red Diamond Key How to Find?
There’s a bit of a gap between when you acquire the blue spade key and the red diamond key. Just keep playing as you normally would until you eventually gain access to the parking garage and, yes, those bloody dogs!
Before you enter the parking garage area it’s worth making sure you’ve got the right tools for the job. If you’ve yet to pick up the shotgun or grenade launcher, depending on which character you’re playing as, head back and grab it. You will need it.
The goal of the parking garage is to gain access to the morgue, which is over the opposite side of the area. To access it, you’ll need to pass through the kennels (joy!) then make a beeline for the door at the end of the corridor. Head to the northern area and you’ll find a wall of cold lockers (the things they store dead people in). There’s a few to open up, but the only one you need to focus on is the second from the left. Inside is not only the Red Diamond Key, but also a nice surprise.