I found a pretty bad bug/glitch.
On Call of the Dead I was playing Sharpshooter, and I picked up a death machine while reloading; however I had Electric Cherry.
The result was after being shocked, the zombies notargetted me.
EDIT: Also before taking this screenshot, Electric Cherry made Romero disappear while playing the "get teddy in box" girl laughing sound effect. But I couldn't screenshot it.