Boss Rush

“

Do you wish to face my challenge?

— Boss Rush initiation dialogue (on repeat attempts)

Progress bar icon

Eye sigil that appears in the background

The Boss Rush is a special event that is activated upon the use of Terminus. Although it can be summoned at any point in the game, it is recommended to be fought after all other bosses are defeated. During the event, every vanilla and Calamity boss spawns sequentially in a predetermined order. The bosses summoned have immensely buffed HP and damage and use modified AI, giving them all similar difficulties despite their usual distance in the game's progression. The Boss Rush can be deactivated at any time by using Terminus again.

Defeating the Boss Rush rewards the player with the Rock, along with any monetary rewards gained from defeating each boss.

Progression

Upon starting the Boss Rush, bosses will spawn in a predetermined order that never changes. Only one boss will spawn at a time; the next boss will spawn once the prior boss is defeated. A total of 44 bosses will spawn during the Boss Rush. The bosses are divided into five Tiers, with each new Tier signified by a status message in the chat and a brief rest period.

If a boss cannot be summoned due to an improper time, the time will be changed to accommodate the boss.

The order is as follows:

Boss Rush Progression

Tier	Boss	Health	Notes	Sounds
Tier 1
	King Slime	300,000 / 420,000 / 535,500		Spawn:
	Desert Scourge	1,650,000 / 2,640,000 / 3,960,000		Spawn:
	Eye of Cthulhu	450,000 / 585,000 / 702,000 / 745,875 / 895,050	Sets the time to night (7:30 PM)	Spawn:
	Crabulon	680,000 / 1,088,000 / 1,632,000	Sets the time to day (4:30 AM)	Spawn:
	Eater of Worlds	690,000 / 966,000 / 1,159,200 / 1,231,650 / 1,477,980		Spawn:
	Brain of Cthulhu	100,000 / 170,000 / 272,000 / 216,750 / 346,800		Spawn:
	The Hive Mind	350,000 / 560,000 / 840,000		Spawn:
	The Perforators	270,000 / 432,000 / 648,000		Spawn:
	Queen Bee	315,000 / 441,000 / 507,150 / 562,275 / 646,616		Spawn:
	Deerclops	315,000 / 535,500 / 642,600 / 682,762 / 819,315		Spawn:
	Skeletron	150,000 / 300,000 / 225,000 / 150,000 / 382,500 / 286,875 / 191,250	Sets the time to night (7:30 PM)	Spawn:
	The Slime God	760,000 / 1,216,000 / 1,824,000	Sets the time to day (4:30 AM)	Spawn:
	Wall of Flesh	450,000 / 630,000 / 756,000 / 803,250 / 936,900	Teleports the player to The Underworld	Teleport: Spawn: Tier 2:
Tier 2
	Queen Slime	150,000 / 240,000 / 288,000 / 306,000 / 367,200	Teleports the player back to the previous location	Teleport: Spawn:
	Cryogen	300,000 / 480,000 / 720,000		Spawn:
	The Twins	275,000 / 412,500 / 495,000 / 525,937 / 631,125	Sets the time to night (7:30 PM)	Spawn:
	Aquatic Scourge	1,000,000 / 1,600,000 / 2,400,000	Sets the time to day (4:30 AM)	Spawn:
	The Destroyer	250,000 / 375,000 / 468,750 / 478,125 / 573,750	Sets the time to night (7:30 PM)	Spawn:
	Brimstone Elemental	780,000 / 1,240,000 / 1,872,000	Sets the time to day (4:30 AM)	Spawn:
	Skeletron Prime	160,000 / 240,000 / 288,000 / 306,000 / 367,200	Sets the time to night (7:30 PM)	Spawn:
	Calamitas Clone	520,000 / 832,000 / 1,248,000	Sets the time to night (7:30 PM)	Spawn:
	Plantera	160,000 / 224,000 / 268,800 / 285,600 / 342,720	Sets the time to day (4:30 AM)	Spawn: Tier 3:
Tier 3
	Leviathan and Anahita	860,000 / 1,376,000 / 2,064,000		Spawn:
	Astrum Aureus	740,000 / 1,184,000 / 1,776,000	Sets the time to night (7:30 PM)	Spawn:
	Golem	130,000 / 195,000 / 219,000 / 248,625 / 272,625	Sets the time to day (4:30 AM)	Spawn:
	The Plaguebringer Goliath	370,000 / 592,000 / 888,000		Spawn:
	Empress of Light	200,000 / 280,000 / 336,000 / 357,000 / 428,400	Sets the time to night (7:30 PM)	Spawn:
	Duke Fishron	290,000 / 348,000 / 487,200 / 443,700 / 621,180	Sets the time to day (4:30 AM)	Spawn:
	Ravager	592,000 / 1,000,000 / 1,500,000		Spawn:
	Lunatic Cultist	220,000 / 275,000 / 330,000 / 350,625 / 420,750		Spawn:
	Astrum Deus	650,000 / 1,040,000 / 1,560,000	Sets the time to night (7:30 PM)	Spawn:
	Moon Lord	310,000 / 465,000 / 558,000 / 592,875 / 711,450		Spawn: Tier 4:
Tier 4
	Profaned Guardians	215,000 / 364,000 / 546,000	Sets the time to day (4:30 AM)	Spawn:
	Dragonfolly	300,000 / 480,000 / 720,000		Spawn:
	Providence, the Profaned Goddess	1,250,000 / 2,000,000 / 3,000,000	Sets the time to day (4:30 AM)	Spawn:
	Ceaseless Void	72,000 / 115,200 / 172,800		Spawn:
	Storm Weaver	500,000 / 800,000 / 1,200,000		Spawn:
	Signus, Envoy of the Devourer	320,000 / 512,000 / 768,000		Spawn:
	Polterghast	325,000 / 520,000 / 780,000		Spawn:
	The Old Duke	400,000 / 640,000 / 960,000		Spawn:
	The Devourer of Gods	1,500,000 / 2,400,000 / 3,600,000		Spawn: Tier 5:
Tier 5
	Yharon, Dragon of Rebirth	740,000 / 1,184,000 / 1,776,000		Spawn:
	Exo Mechs	1,900,000 / 3,040,000 / 4,560,000		Spawn:
	Supreme Witch, Calamitas	900,000 / 1,440,000 / 2,160,000		Spawn: Completion:

Tiers

After beating each tier during the Boss Rush, an animation will play above the player that signifies the beginning of the next tier.

Boss Rush Tier Animations

Notes

• Any effects that change the color of the background will be overridden by the custom background for the event. This includes those for day/night.
• Several bosses are sped up due to the potential speed of the player.
• Despite time being reset to the start of day/night for bosses that can only be fought at day/night, it is still possible to run out of time. In this case, the boss will despawn, time will reset back to day/night and boss will be resummoned with full health.
• All damage taken is increased (where applicable) to a minimum value that increases as the player progresses through the event:
  • Contact damage has a minimum of 240 / 400 which increases by 2 for each boss.
  • Projectile damage has a minimum of 220 / 360 which increases by 1 / 2 for each boss.
• King Slime can spawn Rainbow Slimes and Umbrella Slimes when damaged, even when it is not raining.
• The Eater of Worlds will be immune to all debuffs except Enraged, Kami Flu, and Shellfish Claps, and will take 99.9% less damage for ten seconds after being summoned.
• Golem's head will be immune to damage once detached from its body.
• Bosses that enrage outside of their respective biomes, like The Hive Mind and Providence, will no longer be able to do so.
• Providence and the Empress of Light will use their nighttime/daytime movesets, but will not gain Reactive Damage Reduction nor the significant damage buff.
• If the player is in Death Mode, Astrum Deus' fight will be reverted to its lower difficulty form, where only one of the two split worms in phase 2 need to be defeated.
• Draedon will not do his closing monologue after defeating the last Exo Mech, unlike the regular battle.
  • Additionally, unlike the regular fight, the player will have 20 seconds to choose a Mech before one of the three is immediately chosen for them.
• Several of Supreme Witch, Calamitas' features during Boss Rush are unlike her usual fight.
  • She will not vanish upon reaching 1% HP. Instead, the player will be prompted to finish her off after a delay.
  • She will always appear in her hooded form, regardless of whether she has been defeated or not.
  • Her usual dialogues will not appear.
    • The same applies for Draedon.
  • The Brimstone Witch Town NPC will not despawn.
• Yharon does not spawn the flare bomb ring when defeated.
• Providence and the Wall of Flesh do not create Profaned Rock and Demonite/Crimtane brick squares when defeated.
• The waiting time between the prior boss's death and the next boss spawning is 1 second during Tiers 1 through 3, which is increased to 6 seconds during Tiers 4 and 5.
• All wire-activated mechanisms are disabled during a Boss Rush.
• The bosses in Tier 5 are notably made easier in the Boss Rush compared to their usual fights.
• The health of the bosses during the event only scales up with 2 people in multiplayer.
• Defeating a boss that wasn't defeated prior to the Boss Rush will bring that boss' aftermath and will count that boss as being defeated outside of Boss Rush. The boss will also drop all of its normal loot as if it was defeated normally.
  • If a boss has been defeated prior to Boss Rush, it will only drop Hearts and scaling Healing Potions.
• Killing any creature during this event makes the background eye sigil glow red for a brief moment.
• Any critter, enemy, or boss (excluding Town NPCs) that spawned prior to activating the Boss Rush will immediately despawn.

Tips

• Many health and buff potions, as well as mana for mages should be brought, as the Boss Rush can easily take over twenty minutes.
• Auric Tesla armor is a good choice as it provides a wide array of set bonuses and regenerative effects, with its emphasis on sustain making it particularly useful for the lengthy event.
  • Demonshade armor is also useful if the player is good at avoiding damage and wishes to maximize DPS and speedy boss kills.
• Despite being able to begin the Boss Rush at almost any point in the game, the player should definitely have end-game weapons and equipment before facing it if they hope to succeed.
• Avoiding contact damage with any of the bosses and their projectiles/minions should be prioritized, as they can easily deal over 200 damage even with endgame armor.
• Players should attempt to distance themselves from any floors or other solid tiles after defeating the Exo Mechs, in order to maximize the amount of space available to them once Calamitas spawns and her arena generates.

Trivia

• The themes heard throughout the Boss Rush were composed by the artist CDMusic, with each theme faster and more intense than the last.
  • Ensemble Of Fools plays throughout the entirety of Tier 1 up to the Wall of Flesh.
  • Onslaught Of Beasts plays through Tier 2, up to Plantera.
  • Reign Of Lords plays from Tier 3 until the Boss Rush ends.
  • If the Calamity Music Mod is disabled, the vanilla boss themes will play instead.
    • Boss 1 will play through Tier 1 up until the Wall of Flesh.
    • Boss 4 will play through Tier 2 up until Plantera.
    • Boss 2 will play through Tier 3 up until the Moon Lord.
    • Boss 3 will play through Tier 4 up until Yharon, Dragon of Rebirth.
    • The Moon Lord's theme will play through Tier 5 until the Boss Rush ends.
• Although the identity of the messages' speaker and the background symbol are never confirmed in-game, they can be deduced as being an entity named "Xeroc" through hints and implications in various areas.
  • In the lore mentioned in the Requiem item, Xeroc is a godly figure and is implied to be the most powerful entity in Calamity's story.
    • The Rock, rewarded upon beating the Boss Rush, mentions a "monk" in its tooltip, that references the said lore item.
  • Terminus features the same sigil design that appears in the background of the Boss Rush, and the Boss Rush's progress icon. In the original concept art for Terminus, the sigil is designed to represent various aspects of Xeroc, including its "gaze".
    • The sigil in the background is internally referred to as "XerocEye".
  • The official concept art for Xeroc's pre-ascension design bears the sigil design in various areas, namely the clothing, weapon and the light sigil behind the character.
• The status messages that appear throughout the Boss Rush have the color #FAD54D ●.
• Prior to 2.0.1.003, the boss progression was based on a series of polls that took place in the Calamity Mod Discord server, gauging players' favorite bosses and the ones they found the most difficult, with the resulting total being used to determine the rush's order. The current order is instead based on intended in-game progression.
• Prior to 2.0.2.001, there were Boss Rush Curses that could be enabled in the configuration options, and they were inspired by the Pantheon Bindings from the game Hollow Knight. These Bindings, activated during the boss rush mode in said game, hindered the player character in various ways.

Messages

When starting:

• "...How long has it been? Centuries? Perhaps even a millennia?" [sic]
• "I sank this artifact of mine to the deepest depths of the world to prevent it from being used ever again."
• "Few are aware of its existence, and those who are?"
• "They know that the boundless power it was once able to provide can no longer be taken advantage of."
• "It is a surprise to see there is another who is courageous enough to have retrieved it, particularly given these circumstances."
• "A mortal this time, no less! How interesting..."
• "What exactly is it that made you go out of your way to claim what is now nothing more than a decaying stone tablet?"
• "...Perhaps this is an opportunity. Claiming this relic is no small feat, and I have caught brief glimpses of your journey."
• "You, who claimed this artifact that ended an era on your quest to end another..."
• "Who slew the nameless serpent..." (Only appears if Devourer of Gods has been defeated)
• "Who bested even my old friend, the Phoenix..." (Only appears if Yharon has been defeated)
• "Whose power may match the only mortal who has ever made me doubt my own..." (Only appears if both Exo Mechs and Supreme Witch, Calamitas have been defeated)
• "I wish to test your strength, using fragments of my Primordial Light taking the form of your past foes."
• "It will be no easy task, yet should you prove yourself strong enough, I will have a proposal for you."
• "Do you believe yourself capable of conquering such a challenge?"

On repeat attempts:

• "Do you wish to face my challenge?"

After defeating Tier 1:

• "A passable display so far, but not nearly enough to meet my expectations."
• "Prepare both your body and soul for what has yet to come."

After defeating Tier 2:

• "I wasn't mistaken. You are indeed an admirable warrior."
• "Still, you haven't shown me enough. Shall we escalate things further?"

After defeating Tier 3:

• "Your determination and will to grow stronger... It reminds me of myself, when I was mortal."
• "But the hardest challenges still await. Do not let your guard down, even for a moment."

After defeating Tier 4:

• "The trial will soon reach its climax."
• "Now is the time to display your conviction, and the true extent of your strength and will."
• "Prove to me that you are capable of surpassing even yourself."

After defeating the event:

• "A truly excellent display. I see that I was correct! You indeed may be this world's mightiest warrior. However…"
• "It seems as though even that power... it is not enough. I'm afraid I will not be sharing my proposal with you."
• "Though, as a consolation prize, I wish for you to take this ancient stone I carved from the Aerie."
• "I have long held it as a... keepsake, of sorts."
• "Though you may have failed to meet my requirements, it is unlikely that this will be the only time our paths cross!"
• "Continue to seek greater strength, and when we meet again, perhaps you will have grown enough in power to be worthy."
• "In the meantime, I have my own matters that I must attend to."
• "Farewell, for now.

After defeating the event on repeat attempts:

• "You have proven yourself to be a formidable warrior, yet it is not enough. Seek new heights of power, so that you may one day be worthy."

History

edit

These history sections are still a work-in-progress, and may not yet contain changes relevant to the current version of the Calamity Mod.

• 2.0.3.008:
  • Added brand new dialogue during the event. All dialogue now has a color of #FAD54D ●:

When starting: ...How long has it been? Centuries? Perhaps even a millenia? I sank this artifact of mine to the deepest depths of the world to prevent it from being used ever again. Few are aware of its existence, and those who are? They know that the boundless power it was once able to provide can no longer be taken advantage of. It is a surprise to see there is another who is courageous enough to have retrieved it, particularly given these circumstances. A mortal this time, no less! How interesting… What exactly is it that made you go out of your way to claim what is now nothing more than a decaying stone tablet? ...Perhaps this is an opportunity. Claiming this relic is no small feat, and I have caught brief glimpses of your journey. You, who claimed this artifact that ended an era on your quest to end another… Who slew the nameless serpent… (Only appears if Devourer of Gods has been defeated) Who bested even my old friend, the Phoenix… (Only appears if Yharon has been defeated) Whose power may match the only mortal who has ever made me doubt my own… (Only appears if both Exo Mechs and Supreme Witch, Calamitas have been defeated) I wish to test your strength, using fragments of my Primordial Light taking the form of your past foes. It will be no easy task, yet should you prove yourself strong enough, I will have a proposal for you. Do you believe yourself capable of conquering such a challenge? On repeat attempts: Do you wish to face my challenge? After defeating Tier 1: A passable display so far, but not nearly enough to meet my expectations. Prepare both your body and soul for what has yet to come. After defeating Tier 2: I wasn't mistaken. You are indeed an admirable warrior. Still, you haven't shown me enough. Shall we escalate things further? After defeating Tier 3: Your determination and will to grow stronger... It reminds me of myself, when I was mortal. But the hardest challenges still await. Do not let your guard down, even for a moment. After defeating Tier 4: The trial will soon reach its climax. Now is the time to display your conviction, and the true extent of your strength and will. Prove to me that you are capable of surpassing even yourself. After defeating the event: A truly excellent display. I see that I was correct! You indeed may be this world's mightiest warrior. However… It seems as though even that power... it is not enough. I'm afraid I will not be sharing my proposal with you. Though, as a consolation prize, I wish for you to take this ancient stone I carved from the Aerie. I have long held it as a... keepsake, of sorts. Though you may have failed to meet my requirements, it is unlikely that this will be the only time our paths cross! Continue to seek greater strength, and when we meet again, perhaps you will have grown enough in power to be worthy. In the meantime, I have my own matters that I must attend to. Farewell, for now. After defeating the event on repeat attempts: You have proven yourself to be a formidable warrior, yet it is not enough. Seek new heights of power, so that you may one day be worthy.

• 2.0.3.007: Can now end after any boss placed last, instead of only ending after defeating Supreme Witch, Calamitas.

• 2.0.3.003: Decreased damage floor from 240 / 400 + (2 * stage) to 100 / 160 + (2 * stage).

• 2.0.2.002: Increased Boss Checklist Mod difficulty value from 23.75 to 25.99.

• 2.0.2.001:
  • Added it to Boss Checklist.
  • Crabulon, The Slime God, Aquatic Scourge, Brimstone Elemental, and Plantera now change time to day when spawned.
  • Leviathan and Anahita, The Dragonfolly, Storm Weaver, Polterghast, The Devourer of Gods, Yharon, Dragon of Rebirth, and Exo Mechs no longer change time to day when spawned.
  • Fixed an issue where the second part of the fourth tier transitioning text was misplaced to appear while Polterghast spawned instead of Yharon.
  • Removed Boss Rush Curses.

• 2.0.1.003:
  • Now plays a custom sound while force teleporting the player.
  • Increased tier transition volume.
  • Bosses no longer drop loot or spawn Town NPCs when killed.
  • Added the remaining bosses: Deerclops, Empress of Light, Exo Mechs, and Queen Slime.
  • Re-ordered Boss Rush progression based on boss progression:
    • Tier 1 now contain Pre-Hardmode bosses.
    • Tier 2 now contains bosses after Wall of Flesh, up to Plantera.
    • Tier 3 now contains bosses after Plantera, up to Moon Lord.
    • Tier 4 now contains bosses after Moon Lord, up to The Devourer of Gods.
    • Tier 5 contains the remaining main bosses: Yharon, Exo Mechs, and Supreme Calamitas.
  • Fixed it not teleporting players properly in multiplayer.

• 2.0.1.002:
  • Added boss summoning, tier transitioning, teleporting, and winning sounds.
  • Added tier transitioning animations.
  • Removed the additional cooldown between Brimstone Elemental and Signus.

• 2.0.0.001: Improved the sky shader effect.

• 1.5.1.001:
  • Nerfed boss projectile velocity multiplier from 1.35x to 1.25x.
  • Bosses now inherit most effects from Malice Mode.
  • Now inherits lifesteal nerfs and defense damage buffs from Malice Mode.
  • Now inherits the Shadow Dodge nerf from Revengeance Mode.

• 1.5.0.001:
  • Now disables the use of all boss summoning items.
  • All bosses now use Malice Mode AIs.
  • Resprited the event icon.

• 1.4.5.006:
  • Decreased severity of Immunity Frame curse from 5 seconds to 3.
  • Fixed missing text being written in the chat box.

• 1.4.5.004:
  • Decreased the minimum damage thresholds:
    • Reduced minimum contact damage threshold from 300 / 500 + stage*2 to 240 / 400 + stage*2.
    • Reduced minimum projectile damage threshold from 125 / 150 + stage/2 to 90 / 110 + stage/2.
  • Fixed an issue that caused Calamitas to constantly respawn after being killed.

• 1.4.5.003:
  • Now has an event progress bar.
  • Dash Curse now prevents other mod dashes if they use the vanilla dash delay interval.

• 1.4.5.001:
  • Added The Old Duke in Tier 4.
  • Fixed a bug where killing Eater of Worlds prevented the event from progressing.

• 1.4.4.004: No longer disables mounts.

• 1.4.3.002: All enemies and bosses are now immune to Eutrophication, Exo Freeze, Glacial State, Pearl Aura, Silva Stun, Slow, Temporal Sadness, Tesla Freeze, Time Distortion, and Webbed, and are additionally immune to the Spiteful Candle.

• 1.4.2.109: Bosses and other enemies are now vulnerable to more debuffs, including Spite.

• 1.4.2.106:
  • Bosses and their servants now use Death Mode AI.
  • Each tier now has a damage floor which increases for each wave.

• 1.4.2.105: Now allows flight at all times instead of disabling it for certain fights.

• 1.4.2.101: Now disables Wings during certain fights.

• 1.4.2.003: Bosses fought after nighttime bosses now change the time back to day.

• 1.4.2.001:
  • All enemies now become vulnerable to Ichor and Cursed Inferno.
  • Fixed some enemies not becoming vulnerable to Enraged.

• 1.4.1.002: Fixed an issue that prevented it from progressing in multiplayer.

• 1.4.0.002: Now disables mounts.

• 1.4.0.001: Introduced.