Terraria: Calamity Mod - Simple Boss Progression Flowchart

[Johnny.Danger]

See below for a simplified flow chart for boss progression in Calamity. I prefer this format personally and hope it helps others as well. Best of luck!

[Starting]
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[Pre-boss exploration]
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[Desert Scourge]
- Biome: Desert/Underground Desert
- Tool: Stormlion Mandibles to craft summoning item
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[Eye of Cthulhu]
- Biome: Surface at night
- Tool: Suspicious Looking Eye or wait for natural spawn
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[Crabulon (optional)]
- Biome: Glowing Mushroom biome
- Tool: Decapodita Sprout
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[Eater of Worlds/Brain of Cthulhu]
- Biome: Corruption/Crimson
- Action: Break 3 Shadow Orbs/Crimson Hearts or use Worm Food/Bloody Spine
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[Hive Mind/Perforators]
- Biome: Corruption/Crimson
- Action: Destroy Hive Tumor/Perforator Cyst
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[Skeletron]
- Biome: Dungeon entrance
- Action: Talk to the Old Man at night
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[The Slime God]
- Biome: Anywhere
- Tool: Overloaded Sludge
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[Wall of Flesh]
- Biome: Underworld
- Action: Throw a Guide Voodoo Doll into lava
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[Hardmode]
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[Cryogen]
- Biome: Snow biome
- Tool: Cryo Key
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[The Destroyer]
- Biome: Anywhere (typically Surface)
- Tool: Mechanical Worm
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[Aquatic Scourge]
- Biome: Sulphurous Sea
- Tool: Seafood
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[The Twins]
- Biome: Anywhere (typically Surface)
- Tool: Mechanical Eye
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[Brimstone Elemental]
- Biome: Brimstone Crag
- Tool: Charred Idol (requires one Mechanical Boss defeated)
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[Skeletron Prime]
- Biome: Anywhere (typically Surface)
- Tool: Mechanical Skull
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[Calamitas Clone or Plantera]
- Biome: Anywhere for Calamitas Clone, Jungle for Plantera
- Action: Use Eye of Desolation for Calamitas Clone, break Plantera's Bulb for Plantera
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[Leviathan and Anahita]
- Biome: Ocean
- Action: Fish using a Truffle Worm or wait for natural spawn
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[Astrum Aureus]
- Biome: Astral Infection biome
- Tool: Astral Beacon
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[Golem]
- Biome: Jungle Temple
- Tool: Lihzahrd Power Cell at the Lihzahrd Altar
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[Plaguebringer Goliath]
- Biome: Jungle
- Tool: Abombination
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[Duke Fishron]
- Biome: Ocean
- Action: Fish using a Truffle Worm
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[Empress of Light]
- Biome: Hallow
- Action: Kill a Prismatic Lacewing at night
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[Ravager]
- Biome: Anywhere
- Tool: Death Whistle
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[Lunatic Cultist]
- Biome: Dungeon entrance
- Action: Kill the Cultists after Golem is defeated
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[Astrum Deus (optional)]
- Biome: Astral Infection biome
- Tool: Titan Heart at Astral Beacon
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[Moon Lord]
- Biome: Anywhere
- Action: Defeat Lunatic Cultist and Celestial Pillars
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[Profaned Guardians]
- Biome: Hallow or Underworld
- Tool: Profaned Core
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[Providence, the Profaned Goddess]
- Biome: Hallow or Underworld
- Tool: Profaned Core
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[Storm Weaver]
- Biome: Space
- Tool: Rune of Kos
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[Ceaseless Void]
- Biome: Dungeon
- Tool: Rune of Kos
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[Signus, Envoy of the Devourer]
- Biome: Underworld
- Tool: Rune of Kos
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[Polterghast]
- Biome: Dungeon
- Tool: Necroplasmic Beacon
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[The Old Duke (optional)]
- Biome: Sulphurous Sea
- Tool: Bloodworm
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[The Devourer of Gods]
- Biome: Anywhere
- Tool: Cosmic Worm
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[Yharon, Dragon of Rebirth]
- Biome: Jungle Temple
- Tool: Dragon Egg
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[Supreme Witch, Calamitas]
- Biome: Anywhere
- Tool: Altar of the Accursed
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[Exo Mechs]
- Biome: Anywhere
- Tool: Contact Draedon using the Codebreaker
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[Boss Rush (optional)]
- Biome: Anywhere
- Tool: Terminus
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[Primordial Wyrm (optional)]
- Biome: Abyss
- Tool: Contact Draedon in the Abyss
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[Endgame Activities]