Giant Clam

"A specimen which has developed a grand size, and inexplicably, impressive psychic abilities."

The Giant Clam is a mini boss that rarely spawns in the Sunken Sea after defeating the Desert Scourge, and is generally the first mini boss that the player will encounter. It receives a huge buff during Hardmode. It is initially passive and closed up, but once the player hits it 5 times, the player receives the Clamity debuff, which boosts the spawn rate of Clams and making them aggressive while reducing the other enemies' spawn rate to 0, and the Giant Clam becomes aggressive.

While mostly immobile, it can perform one of 2 moves every 4 seconds. Its most common move is to teleport over the player's head and fall down on them. The other, less common move is to close itself up for a short while, then spawn 3 more Clams.

In Hardmode, it gains 2 new attacks which have a timer of 3 seconds, unrelated to its primary attacks, on top of making its tele-stomp attack faster. Its first attack is to shoot a ring of 6 psychic pearls along with another faster pearl that is always aimed towards the player. Its second attack is to summon a rain of 11 psychic pearls upon the player, which have a gap between them.

It will drop the Sea King if he is not already present in the world and the Desert Scourge has been defeated already. Additionally, Sunken Crates will include Giant Clam's weapons in Hardmode after it has been defeated.

It can be detected with the Lifeform Analyzer.

Trivia

 * The Clamity debuff name is a portmanteau of the word "clam" and the mod's title, "Calamity."