The Arms Dealer is an NPC vendor that will spawn once the following criteria have been met:
- There is an empty house.
- You have at least one bullet firing Gun or Bullet in your inventory (not just stored in a Chest).
If the Arms Dealer is killed, he will only respawn if the above conditions are met again. This means you must place a Gun or Bullet in your inventory. Having them stored in Chests will not fulfill this requirement, and neither will magic guns such as the Space Gun or the Laser Rifle.
 Items sold
Once the Arms Dealer has moved into a house, he will sell the following:
|Musket Ball||7||Always available.|
|Unholy Arrow||40||Every night after defeating the Eater of Worlds or Brain of Cthulhu for the first time (Always available after defeating the Wall of Flesh).|
|Flintlock Pistol||5||Always available.|
|Illegal Gun Parts||25||Only at night.|
|Silver Bullet||15||During a Blood Moon (Always available after defeating the Wall of Flesh).|
|Shotgun||25||After defeating the Wall of Flesh.|
|Empty Bullet||3||After defeating the Wall of Flesh.|
|Stynger Bolt||75||When the player possesses a Stynger.|
|Stake||15||When the player possesses a Stake Launcher.|
|Candy Corn||5||When the player possesses a Candy Corn Rifle.|
|Explosive Jack 'O Lantern||15||When the player possesses a Jack 'O Lantern Launcher.|
|Nurse Hat||3||During Halloween.|
|Nurse Shirt||3||During Halloween.|
|Nurse Pants||3||During Halloween.|
The arms dealer may have any of the following names:
- "Keep your hands off my gun, buddy!"
- "Hey, this ain't a movie, pal. Ammo costs extra."
- "I see you're eyeballing the Minishark. You really don't want to know how it was made."
- "Don't bother with [Name of Demolitionist], I've got all you need right here." (Only if Demolitionist is present.)
- "What's [Name of Demolitionist]'s problem? Does he even realize we sell completely different stuff?" (Only if Demolitionist is present.)
- "Make it quick! I've got a date with [Name of Nurse] in an hour." (Only if Nurse is present.)
- "I want what [Name of Nurse] is sellin'. What do you mean, she doesn't sell anything?" (Only if Nurse is present. Also refers to the fact that the Nurse doesn't sell anything.)
- "[Name of Dryad] is a looker. Too bad she's such a prude." (Only if Dryad is present.)
Only during night:
- "I heard there is a doll that looks very similar to [Name of Guide] somewhere in the underworld. I'd like to put a few rounds in it." (This will be the only message available if Skeletron is defeated, but Wall of Flesh is not.) (This refers to the Guide Voodoo Doll)
Only during a Blood Moon:
- "I love nights like tonight, there is never a shortage of things to kill."
- "Man, it's a good night not to talk to anybody, don't you think, [Name of Player]?" (This is a reference to the NPCs becoming incredibly paranoid, sinister or rude during Blood Moons.)
- The Arms Dealer is very arrogant compared to the other NPCs and seems to have an observant personality, often noticing you (apparently) intend to either buy the Minishark or steal one of his weapons. This, when coupled with the way he speaks, may support that he is based off the traditional gangster. He also seems to have a rivalry with the Demolitionist, as he says his products are better than "fireworks". He also has a crush on the Nurse according to his quotes.
- The name Brimst may be a reference to Brimstone one of the ingredients of gunpowder.
- The name Dante may be a reference to the main character of the Devil May Cry games.
- The name Marquis may be a reference to the guns and ammo broker of Borderlands if read Mar-kiss.
- The Arms Dealer's sprite is very similar to that of the Demolitionist's alpha version sprite.
- The name Darryl may be a reference to Darryl from the popular TV show, The Walking Dead.
- Unlike several other NPCs, who sell their own clothes on Halloween, the Arms Dealer sells the Nurse's clothes, further cementing his unhealthy obsession with her. On a technical level, this is likely because the Nurse does not have a shop interface through which to sell her own clothes.
- Now sells ammunition for newly introduced weapons and Nurse's clothes (during Halloween).
- Now has random name given to him on spawn. His death will be reported with this name. Also other NPCs will use it in their quotes.
- Illegal Gun Parts are sold every night, not just during new moons.
- Silver Bullets and Unholy Arrows are always available after defeating the Wall of Flesh.
- Shotgun added to inventory.
- 1.0.5: Unholy Arrows, Illegal Gun Parts and Silver Bullets added to inventory. Choice of goods become dependent upon time of the day and events.
- Pre-Release: Introduced.