The Merchant is an NPC who appears when all players on a world have a combined total of at least 50 Silver Coins and there is a Home for him to live in. Once the requirements are met, the Merchant will move into the player's world and sell/buy items.
When prompted, the Merchant will say one of the following phrases, depending on the current time:
During the morning, "Lovely morning, wouldn't you say? Was there something you needed?"
During the day, "The sun is high, but my prices are not!"
During the day, "Boy, that sun is hot! I do have some perfectly ventilated armour." (Despite not selling any defensive armour, except the mining helmet.)
During the Evening, "Night will be upon us soon, friend. Make your choices while you can." (Despite selling items at night.)
During a Blood Moon, "Have you seen Chith... Shith... Chat... The big eye?"
During a Blood Moon, "Keep your eye on the prize, buy a lens!"
During a Blood Moon, "Hey, this house is secure, right? Right? <character name>?"
During a Blood Moon, "Not even a Blood Moon can stop capitalism. Let's do business."
During a Blood Moon, "Oh Great. I can hear <Nurse's name> and <Mechanic's name> arguing from here. (Referencing that during a Blood Moon, Female NPCs show tension when they talk, Nurse and Mechanic must be present)
"I hear there's a secret treasure... Oh, never mind."