Merchant

The Merchant is an NPC vendor that will spawn once the following criteria have been met: Destroying the Merchant's home will not cause him to leave, though it will leave him vulnerable to enemies.
 * There is an empty house.
 * All players in the game world have more than between them in their inventories.

Items sold
Once the Merchant has moved into a house, he sells the following:

Note: As with all NPCs, right-clicking an item will allow multiple purchases rather than purchasing it one by one.

Quotes
Note: The Merchant, in contrast to other NPCs, has quotes that change depending upon the time of day.

During morning:
 * "Sword beats paper! Get one today."
 * "Lovely morning, wouldn't you say? Was there something you needed?"
 * "You want apples? You want carrots? You want pineapples? We got torches."

During afternoon:
 * "The sun is high, but my prices are not."
 * "Boy, that sun is hot! I do have some perfectly ventilated armor."
 * "Check out my dirt blocks, they are extra dirty."

During evening:
 * "Ah, they will tell tales of [Name of Player] some day... good ones I'm sure."
 * "Night be upon us soon, friend. Make your choices while you can."
 * "You have no idea how much Dirt Blocks sell for overseas."

During begin of the night:
 * "Kosh, kapleck Mog. Oh sorry, that's klingon for 'Buy something or die.'"
 * "[Name of Player] is it? I've heard good things, friend!"

During midnight:
 * "I wonder if the moon is made of cheese... huh, what? Oh yes, buy something!"
 * "The last guy who was here left some junk... er I mean... treasures!"
 * "Did you say gold? I'll take that off of ya'."

During end of the night
 * "I hear there's a secret treasure... oh never mind."
 * "Angel statue you say? I'm sorry, I'm not a junk dealer." (This quote, however, is a lie as he apparently tries to sell Angel Statues to the Dryad.)

Only during Blood Moon:
 * "Have you seen Chith...Shith.. Chat... The big eye?"
 * "Keep your eye on the prize, buy a lens!"
 * "Oh, great. I can hear [Name of Mechanic] and [Name of Nurse] arguing from here." (Only if Nurse and Mechanic are present.)
 * "Not even a Blood Moon can stop capitalism. Let's do some business."
 * "Hey, this house is secure, right? Right? [Name of Player]?"

When Eye of Cthulhu has NOT been defeated
 * "I hope a scrawny kid like you isn't all that's standing between us and Cthulhu's Eye."
 * "I feel like an evil presence is watching me." (when the natural requirements for Eye of Cthulhu to spawn is acquired)
 * "Look at that shoddy armor you're wearing. Better buy some more healing potions."