Puck is the best-known of the Fae in Nightingale. He appears prominently in the reveal trailer and the gameplay trailer and has been featured repeatedly on the game's social media channels. He acts as a benevolent guide, welcoming Realmwalkers to the lands of Fae as the game begins. By his clothing and friendly attitude, he's presumably a member of the Summer Court of the Fae.
The Realmwalker Compendium entry on The Fae & Magick shows a photograph of Puck with the inscription "Robin Goodfellow, Hobgoblin, Pan... Puck"; these are all aliases for a particular fairy (or group of fairies) from English folklore. Puck is universally described as mischievous, and the name "goodfellow" is a wishful bit of flattery intended to appease him.
Antonio de Torquemada's Jardin Flores Curiosas alleges that Robin-good-fellowes were commonplace in certain homes, which they filled with the sound of music and harmless pranks. He associated them with devils and believed it was the power of God, not their own nature, which restrained them from harming people.
Other sources describe Pucks completing housework in exchange for offerings of bread and milk. Failing to leave out payment would result in its theft and the ongoing displeasure of the Fae.
Goodfellow’s homeland Oberon, or ‘Fairyland’, was described as a land free from vice and disorder, thus he was believed to be fanatical about imposing control on the mortal world through promoting cleanliness and a strong work ethic. For example, it was believed that fairies could help tidy the home; hence Goodfellow was often depicted carrying a broom and supporting domestic workers with their chores. It was also understood that he could enforce order on the household by punishing idle maids who did not meet his high expectations through pinching and nipping them. Consequently, Goodfellow was often praised, or indeed feared, as the strict disciplinarian of the home and its workers.
Puck was known as a shapeshifter who could assume human or animal forms in pursuit of his pranks. He appears in Shakespeare's play A Midsummer Night's Dream.