In Norse mythology, the god of mischief known for his shapeshifting abilities is Loki. Often seen as a trickster, Loki plays complex roles within the myths, sometimes aiding the gods and other times causing chaos. His shapeshifting allows him to take various forms, including animals and even other deities, which underscores his unpredictable nature. Loki's actions ultimately lead to significant events, including the Ragnarok, highlighting the themes of transformation, duality, and the consequences of mischief.