Events

Rain
Fearless Goldfish Warrior In Space in Hardmode: Cloud ElementalCloud Elemental	From Fearless Goldfish Warriors: Tin Helmet From Fearless Goldfish Warriors in Hardmode: Magic Dagger From Angry Nimbuses: Essence of Sunlight From Cloud Elementals: Eye of the Storm Storm Saber Essence of Sunlight From Cloud Elementals after defeating; Providence, the Profaned Goddess: Thunderstorm

Goblin Army
Unique Drops
	From Goblin Warriors: Warblade From Goblin Sorcerers: Plasma Rod From Goblin Summoners: Burning Strife The First Shadowflame

The Calamity Mod adds new drops and mechanics to existing vanilla events, as well as two new unique events.

Blood Moon

Blood Moons can be summoned using the Blood Relic. All enemies during blood moons have a chance to drop Blood Orbs, which are used as an alternative method to craft all vanilla potions as well as most of Calamity's. A blood moon must be active in order for the Drunk Princess to sell the Bloody Mary and for it to grant its beneficial effects. Killing the Lunatic Cultist during this event causes it to drop a unique Lore item. After Moon Lord has been defeated, all enemies have their health increased by 3.5x, and they deal 100 more damage.

Goblin Army

A variety of new loot is dropped by the enemies during a Goblin Army. In Hardmode, the Goblin Sorcerer, Goblin Summoner, and the Shadowflame Apparation are able to inflict the Shadowflame debuff onto the player in Revengeance Mode.

Rain

Rain can be toggled using the Torrential Tear tool. It will also begin to rain upon summoning Storm Weaver when outside of the Boss Rush.

In Death Mode, several additional effects may occur:

Lightning strikes on the Surface.
Icicles fall down in the Snow biome.
Cthulhunadoes spawn instead of Sharknadoes on the Ocean surface.

Acid Rain

Main article: Acid Rain

The Acid Rain is a weather event that has a 1/360000 chance to start every tick after the Eye of Cthulhu has been defeated.

Throughout the duration of the event, all players and enemies in the Sulphurous Sea during the Rain will be inflicted with the Irradiated debuff. Numerous new enemies will spawn in the biome at different points of progression, with the events enemies recieving increases to their stats to make them more suited for each point in progression. The first tier of the event of available after the player has defeated the Eye of Cthulhu, the Second Tier is available after the Aquatic Scourge is defeated and the final tier is available once the player defeats the Polterghast.

Sandstorm

Sandstorms are summonable in Hardmode using the Arid Artifact. In Pre-Hardmode, sandstorms can only begin naturally once the Desert Scourge has been defeated. The Mighty Wind debuff is disabled whenever a boss is alive. Several new drops have been added to the event, and Forbidden Fragments are included in multiple new recipes as well. Furthermore, a new mini boss, the Great Sand Shark, can be summoned using the Sandstorm's Core after Plantera has been defeated.

Sandstorm
Characters	Unique Drops
After defeating Plantera: Great Sand Shark(miniboss)	From Antlion Chargers and Antlion Swarmers: Mandible Bow Mandible Claws From Sand Elementals: Elemental in a Bottle Rare Elemental in a Bottle From Great Sand Sharks: Grand Scale

Pirate Invasion

Three new ranged weapons are dropped during the Pirate Invasion, by Pirate Crossbowers and Pirate Deadeyes.

Pirate Invasion
Unique Drops
From Pirate Crossbowers: Raider's Glory Arbalest From Pirate Deadeyes: Proporse Pistol

Solar Eclipse

Solar Eclipses become ludicrously more difficult after defeating Jungle Dragon, Yharon's first phase. All enemies have their health increased by 32.5x, and they deal 250 more damage. Mothrons slain during a buffed Solar Eclipse will drop Darksun Fragments. All other Solar Eclipse enemies will drop Darksun Fragments after a buffed Mothron has been defeated.

Solar Eclipse
Unique Drops
From Deadly Spheres: Defective Sphere From Reapers and Psychos after Calamitas or Plantera have been defeated: Solar Veil From Mothrons after Jungle Dragon, Yharon's first phase has been defeated, and all other Solar enemies after a buffed Mothron has been defeated.: Darksun Fragment

Frost Moon

The Frost Moon event becomes significantly more difficult after The Devourer of Gods has been defeated. All enemies have their health increased by 6x, and they deal 200 more damage. During the buffed event, Ice Queens have a more difficult AI and will drop Endothermic Energy when slain.

Frost Moon
Unique Drops
From Present Mimics: Holiday Halberd From Ice Queens after The Devourer of Gods has been defeated: Endothermic Energy

Pumpkin Moon

The Pumpkin Moon event becomes significantly more difficult after The Devourer of Gods has been defeated. All enemies have their health increased by 7.5x, and they deal 200 more damage. During the buffed event, Pumpkings have a more difficult AI and will drop Nightmare Fuel when slain.

Pumpkin Moon
Unique Drops
From Pumpkings after The Devourer of Gods has been defeated: Nightmare Fuel

Old One's Army

All enemies except Etherian Goblins, Etherian Goblin Bombers, Etherian Javelin Throwers and Etherian Lightning Bugs are immune to Glacial State, Temporal Sadness, Time Distortion and Webbed. Only one new legendary weapon is dropped from Betsy in Tier 3 (Post-Golem) on Wave 7.

Old One's Army
Unique Drops
From Betsy: Vesuvius

Martian Madness

A magic gun, a rogue bomb, and a unique ranged weapon are dropped by various enemies during the Martian Madness invasion.

Martian Madness
Unique Drops
From Martian Officers, Brain Scramblers, Gray Grunts, Giga Zappers, Martian Engineers, Ray Gunners, and Scutlix Riders: Shock Grenade From Martian Walkers: Wingman From Martian Saucers: Nullification Pistol

Lunar Events

All event enemies spawned during the event drop Lunar Fragments from their respective pillars. The Nebula Pillar enemies during the Lunar Events drop Meld Blobs, a crafting material used for Meld Bars. Every Pillar enemy has a chance to drop their respective Pillar's Fragment.

The Celestial Pillars also require 100 enemies to be defeated in Expert Mode before their shields go down, as compared to the original 150. This can be reverted through the configuration options.

Lunar Events
Unique Drops
From all Nebula Pillar enemies: Nebula Fragment Meld Blob From all Solar Pillar enemies: Solar Fragment From all Vortex Pillar enemies: Vortex Fragment From all Stardust Pillar enemies: Stardust Fragment From Storm Divers: Conference Call

Boss Rush

Main article: Boss Rush

The Boss Rush is a special event activated by using Terminus, obtained either from the Shrine at the bottom of the Abyss or killing Jungle Dragon, Yharon. During the event, all vanilla and Calamity bosses will spawn in a unique sequence, each with their own modified behaviors and buffed stats.

Boss Rush
Unique Drops
From The Devourer of Gods while the Boss Rush is active: Rock

Notes

Players can enable a configuration option to disable event enemy spawns whenever a Town NPC is nearby.

Blood Moon
Unique Drops		For Sale
From all enemies: Blood Orb From Dripplers: Bouncing Eyeball From Blood Zombies after defeating Skeletron: Carnage	From Fishing: Xerocodile	From Drunk Princess: Bloody Mary

v · d · e Game mechanics
Combat	Damage Reduction • Defense damage • Elemental System • Hit Sounds • Immunity frames • Lifesteal • Minions • Proficiency • Rogue • Shortstrike • Taming
Environment	Biome backgrounds • Events • Music • Status messages
Events	22 Bullet Theory • Acid Rain • Boss Rush • Martian Madness • Mechanical Horde • Solar Eclipse • Noxus Eclipse
Items	Alternative crafting ingredients • Charge • Consumable • Crafting stations (By Hand) • Drops • Modifiers • Rarity • Item Classification System • Recipes • Vanilla item recipes
Game	AI • Boss Health Bar • Configuration options • Death Mode • Endings • Fishing • Game controls • Lore • Malice Mode • Nightmare Mode • Revengeance Mode • Vanilla changes
Player	Adrenaline Meter • Aggro • Buffs and Debuffs • Death Prevention • Defense • Rage Meter • Stamina Meter
Other	Cutscenes • Item Upgrade System • Sanity