Players who venture into Core Keeper alone might get bored with various mundane and boring tasks that the game throws at them. However, NPC traders are available to recruit players and build a house for them to make the journey more enjoyable overall. These NPCs offer compensation for any valuable items players receive and provide some much-needed company. However, there are certain requirements that you must meet in order for them to live in a house that you build.
Slime Merchant, Caveling Merchant, and Spirit Merchant are the three NPC merchants that players can recruit in the game. However, only the first two can live in a house, while the latter cannot. Regardless, the requirements players must meet in order to build a house for Slime and Caveling Merchant are listed below:
- The walls of the room you build for traders should not be larger than 8×8.
- The door should be made of wood.
- The room should consist of a bed that the player has never used.
Aside from the above requirements, you also need to place individual summoning items for each vendor. To summon the Slime Merchant you need Slime Oil, while to summon the Caveling Merchant you need Mysterious Idol. Once you’ve built a separate room for both traders, place the summoning item on the floor of each room and leave the location for a brief moment. After a while, both merchant NPCs should appear in their respective rooms.
https://www.gamepur.com/guides/how-to-build-npc-merchant-houses-in-core-keeper How to Build NPC Merchant Houses in Core Keeper