

Type | |
---|---|
Environment | |
AI Type | Bacterium Prime AI |
Damage | 27 |
Max Life | 3100 |
Defense | 9 |
KB Resist | 100% |
Immune to | ![]() |


Type | |
---|---|
Environment | |
AI Type | Bacterium Prime AI |
Damage | 27 |
Max Life | 3100 |
Defense | 9 |
KB Resist | 100% |
Immune to | ![]() |
Coins | 5 |
---|
- Item (Quantity)Rate
Baccilite Ore(Avalon) (15-41)
100%Booger(Avalon) (12-17)
100%Lesser Healing Potion (5-15)
100%Stamina Crystal(Avalon)
25*25%Bacterium Prime Trophy(Avalon)
10*10%Bacterium Prime Mask(Avalon)
14.29*14.29%Treasure Bag(Bacterium Prime)(Avalon)
- From Treasure Bag
Badge of Bacteria(Avalon)
Baccilite Ore(Avalon) (80-111)
Booger(Avalon) (20-40)
Petri Dish(Avalon)
Bacterium Prime Relic(Avalon)


Bacterium Prime is a Pre-Hardmode Contagion-themed boss in Avalon. It is summoned with the Infested Carcass in the Contagion, or by breaking three Sepsis Cells that generate in the Contagion Rings.
Defeating Bacterium Prime is the only way to obtain Boogers.
Bacterium Prime is the Contagion counterpart to the Corruption's Eater of Worlds and the Crimson's Brain of Cthulhu.
While Bacterium Prime is alive, the music Bacterium PrimeFile:Music-Bacterium Prime (Avalon).mp3 will play.
Behaviour
First Phase
Bacterium Prime will advance towards its target, leaving non-damaging gas clouds that inflict the Darkness debuff, as well as the Blackout debuff in Expert mode. Every so often, the boss will perform a curved dash roughly directed at the player, and then continue to leave gas clouds.
Second Phase
When the boss goes below 60% health, its eye will open and it'll speed up slightly, and continue to leave gas clouds while occasionally spewing Bouncy Booger Balls (which drop Boogers after a certain period of time) and Corrosive Mucus (which stays on the ground for a short time after colliding with a tile). If the boss is fought on the surface of the Contagion, it will also spawn Spore Seeds, which grow into mushroom trees that also damage the player.
Achievements


Trivia
- The
Bestiary entry for Bacterium Prime: "This giant eye of Contagion never ceases, never truly closes. Those who fall to its gaze will be just as felled by its plague."