Glorp

Glorps are theorized to be an evolved form of gelatinous cubes that develop over a long period of time being exposed to raw mana in the wild. They live simple lives and are moderately-intelligent. In observing humans and other bipedal races, most of them choose to anthropomorphize themselves.

Attributes

Ability Score Increase. Your Intelligence ability score decreases by 2, and your Intelligence ability score can only ever be higher than 11 if a Wish spell is cast. Your Constitution ability score increases by 1, and two other ability scores of your choice, other than Intelligence, each increase by 1.

Age. Glorps reach maturity approximately two weeks after they become sentient, and are capable of living extremely long periods of time. The oldest member of their species is over 500 years old.  

Creature Type. You are an ooze.

Size. Glorps range in size greatly; you can choose any size from tiny to large.  

Speed. Your base walking speed is 30 feet. If your size is small or smaller, your base walking speed is 25 feet; if your size is large, your base walking speed is 40 feet.  

Languages. Due to your form, you cannot verbally communicate. You can read and write one language that you and the DM decide is appropriate for your character.  

Alter Form. You can cast the Alter Self spell at will.

Alter Size. Once per long rest, you can cast the Enlarge/Reduce spell on yourself only.

Unusual Nature. You do not require air, drink, or sleep.

Water Vulnerability. Due to your form, you are not capable of swimming. If you enter a body of water, you sink straight to the bottom, and can only traverse it by walking.

Thunder Vulnerability. You are vulnerable to Thunder damage.