Water Leech

The Water Leech is a Pre-Hardmode enemy that spawns during the Acid Rain event. It is fairly common and accelerates toward the player while they are submerged and sticking on them. It does not deal contact damage but it will constantly inflict the Bleeding debuff along with the Heavy Bleeding debuff, which reduces player's health by 3 per second in Tier 1, 6 per second in Tier 2, and 12 per second in Tier 3. If the player is not submerged, Water Leeches become invincible and immobile.