Terraria: How to Unlock the Queen Machine Achievement

Terraria‘s most recent updates unveiled a slew of new achievements for players to go after, and no achievement has been more popular than the “Unlock the Queen Machine”, which you can obtain after a series of steps that involve preparation, a major boss fight and some smart thinking for strategy.

“Strategy” being the keyword of choice here, since not only the boss in question is pretty tough (it is a Hardmode boss fight, after all), but even summoning it will demand some dedication from you.

Luckily, that’s what we’re here for — read on to find our guide on how to do everything right and obtain one of Terraria’s most fun achievements.

Mechdusa is a formidable Hardmode boss exclusive to special world seeds that combine the “For the Worthy” and “Remix” features (such as the “getfixedboi” or “Zenith” seed). It is a terrifying fusion of the three mechanical bosses: Skeletron Prime, The Destroyer, and The Twins. Defeating this monstrosity for the first time will grant you the Queen Machine achievement.

Preparation: Summoning and Seeds

Before even facing Mechdusa, you must create the proper context and environment for it to even come out. The process is not difficult to understand, although it is time-consuming:

• The Seed: You must play in a world using the “getfixedboi” seed or a combination of For the Worthy and Remix.
• The Summoning Item: Craft Ocram’s Razor at a Mythril or Orichalcum Anvil by combining:
  • 1x Mechanical Skull
  • 1x Mechanical Eye
  • 1x Mechanical Worm.
• Manual vs. Natural Spawn: You can use Ocram’s Razor anywhere at any time. Alternatively, there is a 1/20 (5%) chance it will spawn naturally at dusk once an altar has been destroyed, provided at least one of its constituent bosses hasn’t been defeated yet.

Recommended Setup

Look, we told you it wasn’t gonna be easy, right? Because this fight involves three bosses at once, your gear and arena are critical to ensure victory.

• Arena: Build a large, long arena (roughly 300×600) filled with platforms, campfires, heart lamps, and star jars.
• Mount: The Black Spot is highly recommended for constant mobility, allowing you to focus your accessory slots on defense and damage rather than movement.
• Weapons:
  • Daedalus Stormbow with Holy Arrows: Excellent for high DPS from a distance.
  • Clinger Staff: A “must-have” for a specific strategy to trap and kill The Destroyer segment quickly.
  • Piercing Weapons: Since Mechdusa is a massive target composed of multiple parts, piercing weapons can hit all three bosses simultaneously.
• Accessories: Focus on defense and dodging. Recommended items include the Worm Scarf, Ankh Shield, Star Veil, Brain of Cthulhu, and Frozen Turtle Shell, all reforged to Warding.
• Buffs: Use every buff available. This includes Wrath, Rage, Inferno, and Red Potions (which provide beneficial buffs in these specific secret seeds).

Combat Strategy

Targeting Priority: There are two main schools of thought for targeting:

1. Keep them together: Most Terraria players recommend saving Skeletron Prime last, as this boss serves as the “anchor”. I guess you could say he’s a “first weakness” of sorts, since Skeletron keeps the Twins and the Destroyer from moving around too much. As they’re all stuck, it makes them all that much easier targets.
2. Go after the Destroyer first: The big guy can be cheesed off by using the Cllinger Staff immediately on its spawn point. Albeit not big in numbers, the staff offers continuous damage, which will allow you to focus on other aspects of the fight.

Execution:

• Phase 1 (The Fusion): As soon as you summon the boss, locate where it spawned on your minimap. If using the Clinger Staff, drop its barrier directly on The Destroyer’s segment.
• Movement: Fly in large circles around the edges of your arena using the Black Spot to avoid Skeletron Prime’s limbs and The Twins’ projectiles.
• Crowd Control: Watch out for the Probes released by The Destroyer. Focus on them occasionally to pick up heart drops for health.
• Phase 2 (Separation): If Skeletron Prime is defeated first, the bosses will separate. The Twins will begin following you normally, and The Destroyer will start burrowing. At this point, focus on Spazmatism (the green eye) first, as its second-phase flamethrower is lethal.

Obtaining the Achievement

The Queen Machine achievement is specifically categorized as a “Challenger” achievement and is awarded the moment the entire combined form is defeated for the first time. Note that defeating Mechdusa does not trigger the “Mecha Mayhem” achievement (which is for defeating the three standard mechanical bosses simultaneously).

Once defeated, Mechdusa will drop the Waffle’s Iron (a guaranteed 100% drop) and Treasure Bags for all three mechanical bosses.

Terraria is available on several platforms, including Windows, PlayStation 3, Xbox 360, PlayStation Vita, iOS, Android, PlayStation 4, Xbox One, macOS, Linux, Nintendo 3DS, Wii U, Nintendo Switch, and even the now-defunct Google Stadia.