Some of these are fairly disturbing.
Space filler, at most.
The top left didn't have a head, and I was too lazy to draw an appropriate one.
Tank head at the bottom was also space filler, along with the other unnecessary faces.
and my humor is weird for your (
edit:) Western standards.
they all have + on their face
To help keep things centered and the correct size.
Notice how I said
help.
Meaning, it might have not.
This was done in 30 minutes at most. I'm no drawing prodigy.