Zombies

Zombies are the main enemy in the game. They are usually very slow, but during the night they get faster, and get more health. They are thus way more dangerous during the night. During the Blood Moon, the zombies will have red eyes, and greatly increased speed and health. At this point they will even outrun a player without speed upgrades.

Even though they are very slow, if they can reach you they will kill you in seconds, especially when there with more than two. So if your tycoon is hasn't got good walls, stay on watch and kill everything coming.

Zombies are the only way to obtain ruby's. With this currency you can buy cool stuff in the ruby store. Although slow, they can be a decent thread when your tycoon is small. They can be really annoying during a PVP fight, making you need to watch two or more enemy's at the same time.

Behavior 

Zombies are simple AI's that focus on the nearest player. The distance to this target player doesn't matter, as when you're alone at a server, all zombies from over the whole map will come to you. They spawn at the beaches and the bay. During the period of one minute before the night, they don't spawn at all. During the Blood Moon normal zombies have greatly increased speed, health and damage. However, this doesn't affect the Chillings.