Chop down your first tree.
Build a house suitable enough for your first town NPC, such as the guide, to move into.
Obtain your first hammer via crafting or otherwise.
Mine your first nugget of ore with a pickaxe.
Discover and smash your first heart crystal underground.
Obtain an anvil made from iron or lead.
Discover a golden chest underground and take a peek at its contents.
Craft a mana crystal out of fallen stars, and consume it.
Equip your first grappling hook.
Defeat the Eye of Cthulhu, an ocular menace who only appears at night.
Using explosives or your trusty hammer, smash a Shadow Orb or Crimson Heart in the evil parts of your world.
Defeat the Eater of Worlds, a massive worm whom dwells in the corruption.
Defeat the Brain of Cthulhu, an enourmous demon brain which haunts the creeping crimson.
Discover a large bee's hive deep in the jungle.
Defeat the Queen Bee, the matriarch of the jungle hives.
Defeat Skeletron, the cursed guardian of the dungeon.
Steal a key from the dungeon's undead denizens, and unlock one of their precious golden chests.
Spelunk deep enough to reach the molten underworld.
Craft a molten pickaxe using the hottest of materials.
Defeat the Wall of Flesh, the master and core of the world who arises after a great, burning sacrifice.
Unleash the ancient spirits of light and darkness across your world, enabling much stronger foes and showering the world with dazzling treasures (and rainbows!).
Smash a demon or crimson altar with a powerful, holy hammer.
Mine a powerful ore that has been newly blessed upon your world.
Equip a pair of wings.
Obtain a boss-summoning item.
Defeat the three nocturnal mechanical menaces: the Twins, the Destroyer, and Skeletron Prime.
Craft a drax or pickaxe axe using hallowed bars, and the souls of the three mechanical bosses.
Mine chlorophyte, an organic ore found deep among the thickest of flora.
Consume a life fruit, which grows in the thick of subterranean jungle grass.
Defeat Plantera, the overgrown monstrosity of the jungle's depths.
Breach the impenetrable walls of the jungle temple.
Defeat Golem, the stone-faced ritualistic idol of the lihzahrd tribe.
Obtain a rare treasure from a difficult monster in the dungeon.
Unlock one of the dungeon's large, mysterious chests with a special key.
Defeat Duke Fishron, mutant terror of the sea.
Defeat the Ancient Cultist, fanatical leader of the dungeon coven.
Defeat the four celestial towers of the moon.
Defeat the Moon Lord.
Survive a blood moon, a nocturnal event where the rivers run red and monsters swarm aplenty.
Defeat King Slime, the lord of all things slimy.
Triumph over a goblin invasion, a ragtag regiment of crude, barbaric, pointy-eared warriors and their shadowflame sorcerers.
Triumph over a pirate invasion, a group of pillagers from the sea out for your booty... and your life!
Survive a solar eclipse, a day darker than night filled with creatures of horror.
Triumph over the frost legion, a festive family of maniacal snowman mobsters.
Triumph over a martian invasion, when beings from out of this world come to scramble your brains and probe you in uncomfortable places.
Reach the 15th wave of a pumpkin moon, where evil lurks among the autumn harvest.
Reach the 15th wave of a frost moon, where the festive season quickly degrades into madness.
Survive the slime rain, where gelatinous organisms fall from the sky in droves.
Have all possible town NPCs living in your world.
Fire a Bee Gun while wearing a full set of Bee Armor.
Stumble into a spider cavern in the underground.
Build or encounter a glowing mushroom field above the surface.
You can only go down from here!
The only way is up!
Do battle against the Twins, the Destroyer, and Skeletron Prime simultaneously and emerge victorious.
Defeat every type of slime there is!
Equip armor or vanity clothing in all three social slots.
Defeat an enemy by running it over with a minecart.
Destroy a total of 10,000 tiles.
Kill a nymph.
Obtain a Terra Blade, forged from the finest blades of light and darkness.
Survive a long fall with just a sliver of health remaining.
Throw a yoyo.
Equip a dye in every possible dye slot.
Obtain the Terrarian.
Spend over 1 gold being treated by the nurse.
Equip a mount.
Obtain a minishark.
Kill the groom.
Kill Doctor Bones.
Fire a rainbow gun while riding on a unicorn.
Command nine summoned minions simultaneously.
Obtain a rainbow rod.
Build a house in a mushroom biome and have the Truffle move in.
Become a victim to a nasty underground trap.
Travel a total of 26.2 miles on foot.
Obtain a golden fishing rod.
Complete your 1st quest for the angler.
Complete your 10th quest for the angler.
Complete your 25th quest for the angler.
Complete your 50th quest for the angler.
Complete a grand total of 200 quests for the angler.
Attain maximum health and mana possible without accessories or buffs.
Defeat every boss in Terraria.
Survive your character's first full night.
Equip armor in all three armor slots: head, chest, and feet.
Craft your first work bench.
Defeat the Empress of Light, responsible for all those flashy lights and glitter.
Defeat Queen Slime, giving the coup-de-grace to the sovereign of all that jiggles.
Defeat the Dreadnautilus, murderous mollusk lurking beneath the surface of the sanguine seas.
Repel the strongest forces the Old One's Army can muster.
Obtain the Zenith, the culmination of a journey forged into the ultimate sword.
Obtain the Terraspark Boots, forged from the finest boots of fire and ice.
Fly a kite on a windy day.
Enter a misty graveyard filled with the surly dead.
Drop a lure in a pool of lava for a pre-fried haul!
Trick a gnome into turning into stone!
Meet with a tenant who's as happy as they possibly can be!
Deliver headpats to the town pet.
Encounter a fairy.
What you're celebrating doesn't matter, just throw a party already!
You were so preoccupied with whether or not you could open the chest that you didn't stop to think if you should.