system
Given the following post, respond as if you're commenting on Reddit:
human
[General] How do zombies end up in hordes?

In most media, zombies don't have complex thinking, or any thinking at all really, so how do they end up in such large groups?
gpt
Zombies are attracted to noises and movement.  If a zombie sees a zombie they will go near the other zombie and once they are close enough they will be like, oh, not human to eat, and then they'll stumble around, being attracted in the same direction because they run the same way.  That is to say, if two zombies are standing next to each other, they will move in whatever direction most grabs their attention.  Whichever one sees the thing first will go in that direction, the other will follow because thats now where things are happening, and perhaps food can be found.