Building a house in Terraria is a must to invite NPCs, and you can't go wrong putting the extra time in on your own shelter as well!
Terraria: NPCs List of Requirements & Who Can Move in My first base, which is focused on functionality and ease of building. I am not proud of its aesthetics, but it shows all but a few of the NPCs who can move into the world. NPCs (Non-Player Characters) tend to be friendly, help...