Clothier

The Clothier is an NPC vendor who sells only Vanity items (items that do not provide enhancements to your character, and are for aesthetic value only).

The Clothier is the same character as the Old Man who guards the Dungeon before Skeletron is defeated. After you defeat Skeletron, you will have freed the Old Man from his curse, wherein he will disappear from the Dungeon entrance. Once a suitable vacant house is available, he will spawn and sell items. His clothes are no longer tattered, his eyes have turned blue, and he is wearing a red hat.

If the Clothier is killed, he will drop the Red Hat, another Vanity item. Since players can not harm NPCs with weapons, only enemies, Dart Traps, Boulders or lava can kill him. Note that lava of sufficient depth may also destroy the Hat, though. Additionally, the Clothier has a voodoo doll variant, named the Clothier Voodoo Doll, that when equipped allows you to kill him (similar to the Guide Voodoo Doll) and summon Skeletron.

After being freed, he fires a dark magical skull similar to the Book of Skulls at any nearby enemies. In Hardmode, these skulls inflict enemies with Shadowflame.

Hardmode Inventory
These items are sold in addition to the regular inventory, but are only available after hardmode has been unlocked.

Names
The clothier may have any of the following names:

Tips

 * Placing a shallow Lava pit in the floor of the Clothier's house (eg. by pouring one Lava Bucket into an 8 or 9-tile long horizontal recession of one tile height) will cause the Clothier to die and respawn often, leaving behind the Red Hat each time, which can be sold for each (or worn).
 * If you have the clothier voodoo doll equipped, making him die either by lava, or by monsters will spawn Skeletron at night

Quotes

 * "T'were I younger, I would ask [Name of Nurse] out. I used to be quite the lady killer." (Only if Nurse is present)
 * "Thanks again for freeing me from my curse. Felt like something jumped up and bit me" (Reference to Forrest Gump)
 * "Being cursed was lonely, so I once made a friend out of leather. I named him Wilson." (Reference to Cast Away)
 * "Mama always said I would make a great tailor." (Reference to Forrest Gump)
 * "That Red Hat of yours looks familiar..." (When wearing Red Hat only)
 * "Life's like a box of clothes, you never know what you are gonna wear!" (Reference to Forrest Gump)
 * "I have vague memories of tying a woman up and throwing her in a dungeon." (If Mechanic is not housed, reference to how the Mechanic is found tied up inside of the Dungeon.)
 * "Of course embroidery is hard! If it wasn't hard, no one would do it! That's what makes it great." (This is a mock up of line from A League of Their Own)
 * "I know everything there is to know about the clotherin' business." (Reference to Forrest Gump)
 * "I'll give you a discount on your wears if you can convince [Name of Truffle] to come over for a ... sizing." (Only if Truffle is present)

During a Blood Moon:
 * "... We have a problem! It's a blood moon out there!" (Reference to Apollo 13)

Trivia

 * Most of the Clothier's dialogues refer to movies starring Tom Hanks. The movies are "Cast Away", "Forrest Gump", "The Ladykillers", "Apollo 13" (IMDb links).
 * Sometimes, the Merchant and the Clothier might have the same name "Alfred", but this is a rare sight.