Giant Amoeba
CREATURE 1These blobs of nearly transparent protoplasm are identical in form and behavior to the microscopic creatures from which they have evolved, except their outlandish size makes them all the more dangerous. Unlike slimes, puddings, and other deadly oozes, giant amoebas have an outer membrane that contains their internal structures, making them more susceptible to slashing weapons than their amorphous kin. However, this membrane is also extremely flexible and permeable, allowing them to surround prey and absorb it, suffocating and slowly digesting it in the amoeba's acidic fluids.
A giant amoeba can sense nearby creatures through vibration and air or water movement.
1d4 bludgeoning plus 1d4 acid, DC 17 basic Fortitude
The monster deals the listed amount of damage to any number of creatures Grabbed or Restrained by it. Each of those creatures can attempt a basic Fortitude save with the listed DC.
A giant amoeba's acid damages only organic material-not metal, stone, or other inorganic substances.
The monster can instead use Grab and choose one creature it's grabbing or restraining with an appendage that has Grab to automatically extend that condition to the end of the monster's next turn.