A mutant, Moonstar originally possessed the psionic/psychic ability to telepathically create illusions of her opponents' fears or wishes. She later developed a wide range of psionic and energy manipulation powers. She also developed some magical abilities after a series of adventures in Asgard. She was a member of the X-Men's 1980s junior team the New Mutants and, after a long absence, its reincarnation X-Force. She was also a member of the X-Men, Young X-Men and Fearless Defenders. She was depowered after Decimation. She regained her powers after being infected with, then cured of Warlock's transmode virus by Dark Beast. She regained her Valkyrie powers after making a deal with Hela.