Ectoplasm

Ectoplasm is an uncommon material in Blox Fruits that players farm from enemies on the Cursed Ship in the Second Sea, making it a regular grind item for midgame progression. It is used for crafting the Skull Guitar, upgrading the Midnight Blade, and unlocking titles like The Ghost, Ruler of Night, and Lonely Reaper, so collecting it has both combat and completion value.