Monster may describe a mythological or legendary creature (such as a dragon or griffin) or it may describe an entity of unusual proportions, physical (giant) or in what the creature does (violation of morality, an act believed wrongful). A monster may indicate a warning or a miracle. Mutations may prove beneficial or harmful.
Frankenstein's monster - animated organic construction
zombies - reanimated dead
King Kong - giant ape
Godzilla - mutated giant aquatic creature
Werewolves - shapeshifters, wolf-persons
Vampires - blood drinkers
ogres - large humanoid creature, man eater
giants - large persons
mutants - genetically changed creatures
mermaids - fish-persons
witches - magic practioners, herbalists, healers
elves - race of godlike creatures
imps - mischievous faery creatures
Further study:
Monster Wiki
Imps
Monstropedia
