Calamity Mod Wiki
Cosmic Viper Engine
  • Cosmic Viper Engine.png
Stack digit 1.png
TypeWeaponCrafting material
Damage138 Summon
Knockback6 (Average)
Use time9 Very Fast
TooltipSummons a cosmic gunship to shoot down your foes
Grants BuffCosmic Viper (buff)Cosmic Viper
Buff tooltipThe cosmic gunship will protect you
Inflicts DebuffGod Slayer InfernoGod Slayer Inferno
100% chance

Debuff duration3 seconds (Concussion Missile)
2 seconds (Homing, Splitting Rocket)
1 second (Shrapnel)
Debuff tooltipYour flesh is burning off
RarityRarity Level: 14
Sell 28 Gold Coin.png
Summons Minion
Cosmic Gunship
Cosmic Gunship.png

The Cosmic Viper Engine is a craftable post-Moon Lord summon weapon that is an upgrade to the Tactical Plague Engine. It summons a Cosmic Gunship that fires the following projectiles:

Projectile Description
Concussion Missile Concussion Missile An accurate fast missile that deals 150% of the weapon’s damage
Homing Rocket Homing Rocket An insanely fast homing rocket
Splitting Rocket Splitting Rocket An insanely fast homing rocket that splits into four Cosmic Shrapnelsshrapnels in random directions when getting close to an enemy. Shrapnels deal 25% damage.

Its best modifier is Ruthless. The Mythical modifier provides the widest array of stat bonuses, but these primarily affect the initial summon rather than the resulting minion. Additionally, minions cannot deal critical hits. The only lasting advantage a Mythical Cosmic Viper Engine has over a Ruthless one is knockback.



Crafting Station
Cosmic AnvilCosmic Anvil
Tactical Plague EngineTactical Plague Engine1
Exodium ClusterExodium Cluster20
Cosmilite BarCosmilite Bar10
Cosmic Viper EngineCosmic Viper Engine1

Used in[]


  • The "Viper" in this weapon's name is a reference to "Vic Viper", the protagonist of the space shooter game series Gradius.