21 hours ago, faatal said:Zombies only attack blocks that are in the way of them getting to what they want. What they want is flesh.
Sometimes, however, the air seems to get in their way. Anyway, you might get the impression when zombies just stop and try to hit the air during the horde. Oddly enough, a block underneath them takes damage when they do that.
You can see this behavior in this video at 28:20: https://www.youtube.com/watch?v=NIDnCjmD-uE
Moe punches the air instead of attacking the player. At 29:10 a business man also starts swinging.