The trickster god in Norse mythology known for shape-shifting is Loki. Loki embodies mischief and chaos, often causing trouble for both gods and mortals. His cunning and unpredictable nature enable him to transform into various forms, including animals and even inanimate objects. Despite his relationships with other gods, he ultimately plays a critical role in Ragnarok, the end of the world in Norse mythology. His character highlights the ambiguity of morality, as he can be both a helpful ally and a dangerous foe.