Monster Physiology, hmm? Well, as the old saying goes, "In order to kill a monster, sometimes you must become one yourself." As for what this sort of transformation power does exactly, it allows one to transform the user to take on the form of a monster, a creature that is often hideous and may produce fear or cause physical harm by either it's appearance or it's actions.
The word "Monster" derives from the Latin word "monstrum", an aberrant occurrence, usually biological, that was taken as a sign that something was wrong within the natural order. The word connotes something wrong or evil; a monster is generally morally objectionable, physically or psychologically hideous, and/or a freak of nature. Sometimes, this sort of ability is also known as Monster Form, Monster Mimicry, or Monstrous Physiology.
Monster Physiology works as a physical superpower, due to using this ability will cause the user to physically change and alter their form into that of a monstrous creature, giving the user access to the following abilities listed below here:
-Enhanced Condition or Supernatural Condition
---Enhanced Durability/Invulnerability
---Enhanced Endurance
---Enhanced Strength
-Fear Inducement
-Supernaturally Dense Tissue
However, having the ability to transform into a monster tends to have a few drawbacks. For example, you may lose sentience while you're in that transformed physical state, making you act more prone out of instinct. Second, transforming into a monster might be difficult, due to you possibly experiencing a painful transformation, feeling every part of your body, from your bones to your own flesh, tearing apart, rearranging, and repairing itself to fit your new intimidating physique. Also, you could cause widespread panic if you're seen by the public, even if you're trying to tell them that you're one of the "good guys".
Now, I understand that you're thinking that monsters take on various different forms throughout different types of media. So to counteract this problem, I will be setting up 3 different choices for various monsters; Science Monster Physiology, Cryptid Monster Physiology, and Mythical Monster Physiology.