The predator Slime can move through a space as narrow as 1 inch wide without squeezing as long as they are naked, and carry no gear.The exceptions are currency, items and certain weapons.

The Predator Slime can climb difficult surfaces, including upside down on ceilings, without needing to make an ability check.

As a slime you don't have real eyes. Instead you have blindsight up to 60ft further than that you are completely blind. 

As a slime you also have the ability to store items 1d6+constitution modifier adding 1d6 every five levels or 1d3+constitution modifier friendly animals or people inside your body safely or you can engulf a hostile creature within 5ft of you. You must succeed a grapple check to engulf them.

Once engulfed you are no longer grappling the creature. Once engulfed you can choose to hold the creature or devour them. If you choose to devour the creature they take 1d6+con modifier+player level acid damage or half damage on successful fortitude save per round target creature remains engulfed.

Each round before taking damage the engulfed creature can try and escape by making a contest skill check. Athletics(strength) +acrobatics(dexterity) verses the predator Slime's athletics(strength)+con modifier+player level.

Immune to slashing and piercing damage
Resistant to bludgeon
Weak to ice, psychic, frightened , charm, and magical weapons.
Immune to blind, exhaustion, prone

As a slime you must eat one living Humanoid per in game month or half your stats. If you fail to do so for a second month half your stats again you lose x days after start of the second month+player level hp and a third month missed you are revealed as a slime and can't maintain your form, carry or wear anything. A fourth month missed is instant death.