Monsters are physical creatures born either of magic, alien worlds, other dimensions or other means. They are not spiritual or ghostlike and thus can be fought and even slain by mortals such as humans, though often their terrible features and strange abilities frighten mortals to the extent only hardened warriors, great heroes or demigods truly dare to challenge them.

Monsters differ from ghosts, demons and the like by being physical and capable of destruction, they also can not possess others (though they may have psychic abilities or parasitic qualities). However, they share the common trait of going against nature or the natural order, which is why they are feared.

Monsters can be extremely mutated humans or animals (if they display superhuman abilities), extra-dimensional or alien creatures (providing they are not spiritual in nature) or even minor mystical creatures that are nevertheless shown to have significant weakness and are capable of being combatted without the aid of gods or higher-powers (such as the physical undead, which could include vampires and zombies).

Under no circumstances shall you add simply disfigured or deformed individuals (who do not have any superhuman abilities) or simply "scary looking" creatures - they must show themselves to have strange and often frightening traits not found in nature as we currently understand it.

If in doubt be sure to ask (also while they may be against nature please refrain from adding Artificial Intelligence (such as robots, etc.) to this category as they are not truly monsters in the traditional sense - though fantasy variants such as Frankenstein's Monster or Golems may qualify).

IMPORTANT NOTICE: please do NOT add "monster" if an article is already under Demon, also do not add Deities or Cosmic Entities (as monsters are not immortal nor godlike in scale). Also, this category is only for monsters by visual appearance, not monsters by characterization, for they instead fall under the Pure Evil category. However, villains can be both monsters and Pure Evil if they meet the correct criterias.