|Alchemist||After beating Eye of Cthulhu||Utility pots (teleport, heal, mana); some different materials.|
|Brewer||After beating Eye of Cthulhu||Pots from vanilla and a lot of other mods.|
|Jeweler||After beating Eye of Cthulhu||Gems, bands, sturdy fossils. Has an Arena Shop with arena buffs and such.|
|Architect||If you have any 3 NPCs present||Blocks, furniture and different crafting stations.|
|Operator||After beating Eater of Worlds / Brain of Cthulhu and having Wing of The World placed in empty house||Boss drops and EGO equipment; Treasure Bags if not turned off in config.|
|Musician||After beating Skeletron||Music boxes, including modded ones.|
|Young Brewer||Hardmode. Alchemist and Brewer are alive or||Potion-combinations, flasks and some other stuff.|
|Explorer||If certain conditions are met||Explorer's Brew, end-game materials, recipes for powerful items and ammo for them.|
|Tinkerer||After beating Eye of Cthulhu||Sells accessories. Using Paper Tubes will unlock different ones for you to buy from his shop.|
Explorer will not spawn naturally by herself. You need to find a way of spawning her. Torn Notes, dropped from vanilla bosses, will help you. Make sure to thoroughly read all of them.
Message you get after beating Moon Lord for the first time and top spoiler in #spoilers channel (Discord) can help too.
GIF-Instruction for summoning Explorer (use it only if you can't figure this out): [Boop]