First, I took a screenshot from just Springtrap, with no zombie in it.
The zombie head's from a legit zombie. I just put it in there and used the advanced bone tool (from the workshop) to resize his limbs to the point where they're invisible. There were some leftovers from the shoulders, but I'll talk about those later.
Then I spawned a burned corpse which I used as the zombie's body, since the zombie's torso would usually stick out of the back of Springtrap's head.
I took a second screenshot.

Then I used paint.net to replace all of the zombie's shoulder's leftovers in the second screenshot with parts from the image I took of Springtrap without a body inside of him, and done.

how did yo put the zombie in the suit?

It's... pretty obvious.

I FOUND SOMEONE INSIDE THE SUIT!!!

sup bruh

Thanks

If you're having troubles with the rest of the zombie sticking out and being visible on the screenshot, you can try these two things (I used them both for this):
1. Resize the limbs with an inflator or bone tool
2. Take two screenshots, one without a dead guy inside and one with dead guy inside. Open the folder containing your screenshots (rightclick on g-mod in your library, show screenshots, then show on disk), close Steam entirely,
and use a paint tool to copy certain spots from the screenshot without dead guy to the screenshot with the dead guy, leaving only the parts you want in the picture behind.

Also, I used a classic zombie for the head and a burnt corpse for the body.

Nice addition of the dead guy inside. i tried using a fast zombie headcrabless, but the face is the forehead XD. anyways, nice picture.

Then you don't get the reference. :p
Bruh is a funny pronounciation of bro, btw. If you've really never heard it before.

I dont really know what bruh is?