What are the best NPC housing designs for maximizing happiness in Terraria?

To maximize NPC happiness in Terraria, you need to understand the mechanics of the happiness system and how it affects NPCs. NPC happiness is determined by two main factors: the biome they live in and the neighbors they have nearby. Each NPC has preferred biomes and neighbors, and being in a biome they dislike or having neighbors they dislike will reduce their happiness. High happiness leads to discounts on items they sell and, in some cases, access to unique items like the Pylon system, which allows fast travel between biomes.

To start, you need to know the preferences of each NPC. For example, the Guide prefers the Forest biome and likes living with the Zoologist or Clothier. The Merchant prefers the Forest biome and likes the Golfer and Nurse. The Arms Dealer prefers the Desert biome and likes the Nurse and Steampunker. The Goblin Tinkerer prefers the Underground biome and likes the Mechanic and Dye Trader. These preferences are key to setting up your housing.

Step one is to identify the biomes you want to use for housing. The Forest biome is the easiest to start with, as it is the default biome and many NPCs like it. You can create artificial biomes by placing specific blocks or walls. For example, placing 1,500 Sand Blocks will create a Desert biome, and placing 200 Jungle Grass Blocks will create a Jungle biome. This allows you to build housing in any biome you need.

Step two is to build small, efficient houses for your NPCs. Each house should be at least 6 blocks wide and 10 blocks tall, with walls, a chair, a table, and a light source. You can stack houses vertically or horizontally, but make sure each NPC has their own space. Avoid placing too many NPCs in one area, as overcrowding reduces happiness.

Step three is to pair NPCs based on their preferences. For example, place the Arms Dealer and Nurse in the Desert biome, as they like each other and the biome. Place the Goblin Tinkerer and Mechanic in the Underground biome for the same reason. This pairing ensures high happiness and unlocks the Pylon system for fast travel.

Important tips include avoiding placing NPCs in biomes they dislike. For example, the Dryad dislikes the Desert biome, and the Arms Dealer dislikes the Snow biome. Also, avoid placing NPCs near enemies or in dangerous areas, as this can reduce their happiness. Use background walls to prevent enemy spawns and ensure safety.

Common mistakes include overcrowding NPCs in one biome or ignoring their preferences. For example, placing all NPCs in the Forest biome without considering their neighbor preferences will lead to low happiness. Another mistake is not using the Pylon system effectively. Once you unlock a Pylon, place it in a central location for easy access.

Advanced techniques include creating hybrid biomes. For example, you can create a Hallow Desert biome by placing Pearlstone Blocks in a Desert biome. This allows NPCs who like the Hallow and Desert biomes to live together. You can also use teleporters to connect different biomes, making it easier to manage NPC happiness.

Resource requirements include wood, stone, and biome-specific blocks. For example, creating a Desert biome requires Sand Blocks, while creating a Jungle biome requires Jungle Grass Seeds. Preparation involves gathering these resources and planning your housing layout.

Class and equipment considerations are minimal for housing, but having a good pickaxe and building tools like the Architect Gizmo Pack can speed up construction. Use platforms and ropes to access higher areas and build efficiently.

Specific examples include setting up a Forest biome with the Guide, Zoologist, and Merchant. Place the Guide and Zoologist in one house and the Merchant in a nearby house. This setup ensures high happiness and unlocks the Forest Pylon. Another example is setting up a Desert biome with the Arms Dealer, Nurse, and Steampunker. Place the Arms Dealer and Nurse in one house and the Steampunker in a nearby house. This setup ensures high happiness and unlocks the Desert Pylon.

By following these steps and tips, you can maximize NPC happiness in Terraria, unlock the Pylon system, and enjoy discounts and unique items. Proper planning and understanding of NPC preferences are key to success.