Which boss should I fight first?

The Eye of Cthulhu is the canonical first boss. After that, depending on whether your world is Corruption or Crimson, fight the Eater of Worlds or Brain of Cthulhu, then Skeletron, then the Wall of Flesh.

How do I unlock Hardmode?

Defeat the Wall of Flesh in the Underworld. That transitions the entire world into Hardmode, adding new ores, enemies, and biomes — and a sharp difficulty jump. Hardmode can't be reversed, so gear up before you commit.

Which mechanical boss should I fight first?

The Twins, the Destroyer, and Skeletron Prime can be tackled in any order. The usual approach is to pick the easiest for your build, defeat it, use the rewards to upgrade gear, and repeat. Beating all three causes the Plantera bulb to grow in the Jungle.

Who's the final boss?

Moon Lord. After defeating Golem and the Lunatic Cultist, the Lunar Events begin — destroy the four Celestial Pillars and Moon Lord appears. It's effectively Terraria's final boss and the toughest fight in the game.

Terraria Boss Order｜Pre-Hardmode to Hardmode Progression Route

Progression Has Two Phases

Terraria's progression is split by the Wall of Flesh kill — pre-Hardmode and Hardmode. Each boss kill unlocks materials, gear, and new threats, expanding what you can explore.

Many bosses have prerequisites and can't be summoned out of order. Following the recommended route below keeps you unblocked. Bosses in parentheses are optional and can be skipped without breaking progression.

Pre-Hardmode Boss Order

1

Eye of Cthulhu

The first real gate. Summonable manually with a Suspicious Looking Eye. Gear up with ore armor before engaging.
2

Eater of Worlds or Brain of Cthulhu

Eater in Corruption worlds, Brain in Crimson — only one spawns per world.
3

Skeletron

Talk to the Old Man at the Dungeon entrance at night to fight. Required to enter the Dungeon.
4

Wall of Flesh

Summoned by throwing a Guide Voodoo Doll into Underworld lava. Defeating it unlocks Hardmode. Be fully geared first.

King Slime and Queen Bee are optional and can be skipped. But Skeletron is required to enter the Dungeon. Hardmode can't be reversed once you beat the Wall of Flesh, so confirm your gear is ready before you swing.

Hardmode Boss Order

The world levels up after WoF. From here, progression unlocks in this order.

Boss	Prerequisites and Notes	Status
Queen Slime	Optional. Summoned in Hallow biome	Optional
Three mechanical bosses	Twins, Destroyer, Skeletron Prime. Any order, all required	Required
Plantera	Summoned from a Jungle bulb after the three mech bosses fall	Required
Golem	Lihzahrd Temple in the Jungle opens after Plantera	Required
Empress of Light / Duke Fishron	Optional, high-difficulty bosses	Optional
Lunatic Cultist → Moon Lord	Appears after Golem; destroy four pillars for the final boss	Required

Any mechanical boss is fine to start with. Pick the easiest for your build, defeat it, upgrade gear with the drops, and clear the other two. Updating your kit at every tier is the safest way to clear Hardmode.

Gear and Gold Prep

Updating gear before each boss is essential. Class-specific gear is covered in the Class and Build Guide, and funding potions and arena builds is covered in the Money Making Guide. New players should start with the Beginner Guide.

★Honest Take: Knowing the Order Changes the Experience

Honestly, knowing the next boss to tackle is the biggest single quality-of-life upgrade in mid-game Terraria. Going in blind leads to constant stalling; following the recommended route gives you a clear next goal at every step and makes the power curve feel great. Don't skip the gear updates between tiers — it really is the shortest path.