This list of mythical creatures that begin with this letter and I am constantly gathering information from each continent, and is continually being updated.
Goblin (Medieval)
A goblin is a small, grotesque, monstrous creature that appears in the folklore of multiple European cultures. First attested in stories from the Middle Ages, they are ascribed conflicting abilities, temperaments, and appearances depending on the story and country of origin, ranging from mischievous household spirits to malicious, bestial thieves. They often have magical abilities similar to a fairy or demon, such as the ability to shapeshift.
Similar creatures include brownies, dwarves, duendes, gnomes, imps, leprechauns, and kobolds, but it is also commonly used as a blanket term for all small, fay creatures. The term is sometimes expanded to include goblin-like creatures of other cultures, such as the pukwudgie, dokkaebi, or ifrit.