Drippler

Nothing summons it directly and it needs no progression behind it. It simply turns up among the other blood moon spawns once the sky goes red, hovers above the ground and drifts toward you. It weighs almost nothing, so any weapon with knockback keeps one pinned across the screen for as long as you care to keep swinging. If a blood moon feels dangerous, this is not the reason.

• When the night ends they lose interest, float off and disappear. Chasing stragglers for drops after dawn is wasted effort.
• A Drippler Statue will produce them at any hour, but statue spawns are stingy: the rare drops are off the table, the Bloody Tear cannot appear at all, and anything a trap kills gives you nothing.
• It fills the same slot as a Blood Zombie, arriving on the same nights and leaving much the same loot behind, so a farm built for one catches both.
• The bestiary calls it a knot of demon eyes, yet it never drops lenses.