Spawn

Spawning is when your character, a monster, or an NPC appears in a world.

A spawn point is the location where your character first appears in the world. This point can be changed by using a Bed. If you use a Magic Mirror you will teleport to your spawn point, whether it is the world's original spawn point or one you have set with a bed. If you set a spawn point to a bed and the bed is destroyed, your spawn point will be returned to the original place.

Monsters spawn differently from the player. Each monster has certain areas and circumstances in which they can spawn. Monsters only spawn off-screen and have different spawn rates. NPCs will help lower the spawn rate of monsters near their homes. Placing walls and adding light will also stop monsters spawning in an area.

Holding a Water Candle, using a Battle Potion, or during a Blood Moon, monster spawn rate will be increased.

NPCs will spawn once certain critea are met. As of 1.0.6, each NPC requires a room of their own to spawn. This room must have a door, at least one Comfort Object, at least one Flat Surface, and a light source that fills the room. They will spawn close to their home, but have been known to get stuck down caves and holes before finally settling into their new homes.