Ethan is a stocky, unassuming boy who dislikes baseball due to his low self-esteem but plays it to maintain a connection with his father following his mother's death. Thrust into an epic quest when a giant clam names him the champion to save the universe, he slowly gains confidence. He relies on his friends and a catcher's manual to travel through the magical Summerlands.

Jennifer T. is Ethan's fiercely loyal best friend and teammate. Though she projects outward confidence and determination, she internally struggles with a sense of not fully belonging anywhere. A talented pitcher, she utilizes practical knowledge from an old repair manual to overcome supernatural obstacles.

Coyote is an ancient trickster god drawn from Indigenous American mythology, known as the Changer. Believing he can remake existence better than the original gods, he launches a selfish crusade to poison the Tree of Worlds. He exploits the desires and weaknesses of others through deceptive bargains to achieve his destructive goals.

Thor is a large, physically strong teammate of Ethan and Jennifer T. who firmly believes he is a highly sophisticated android. He often feels out of place in the human world but discovers he possesses a natural affinity for shadowtail magic. This rare ability allows him to travel between parallel worlds alongside his friends.

Mr. Feld is Ethan's father, a widower and brilliant engineer who invented an indestructible airship material. He attempts to connect with his son through baseball, unaware of Ethan's deep insecurities. His analytical mind struggles to comprehend the magical reality of the Summerlands after his abduction.

Cutbelly is a 756-year-old werefox and a shadowtail capable of leaping across the invisible branches of the Tree of Worlds. He serves as Ethan's initial guide to the multiverse, delivering the prophecy that sets the boy's epic journey in motion.

Cinquefoil is a noble leader of a toddler-sized faerie tribe in the Summerlands whose home has been decimated by Coyote's chaos. He joins Ethan's party to guide them toward the well of the Tree of Worlds, providing crucial lore and strategic advice along the way.

Taffy is a gentle, apelike sasquatch who has been kept as a prisoner and pet by a massive giant for centuries. Burdened by heavy guilt over past choices that separated her from her family, she proves to be a valuable, if melancholic, addition to Ethan's traveling party.

Chiron Brown is a legendary, otherworldly baseball recruiter who acts as a mystical guide for talented players. He appears seemingly out of nowhere to offer cryptic advice and key items to the young heroes when they need direction the most.

Spider-Rose is a fairy princess who was locked away by her own people after making a disastrous bargain with Coyote to introduce the designated-hitter rule to baseball. Her controversial choice was driven by a deep sense of loneliness, complicating Jennifer T.'s initial judgment of her.

Grim is a young giant enslaved by a faerie tribe and bound by a magical curse to guard their hoard of lost items. Despite his aggressive introduction, he shows a willingness to negotiate and strike deals with Ethan to escape his miserable servitude.

Rodrigo is a famous, Cuban-born baseball legend whose career was relegated to the role of designated hitter following severe knee injuries. Disillusioned with his legacy, he is reluctantly recruited by the children to lend his immense batting power to their world-saving team.

Padfoot is an operative for Coyote who uses the mundane disguise of a businessman to interact with the human world. Beneath his suit, he is a sharp-toothed, furry beast tasked with securing the engineering materials necessary for Coyote's apocalyptic plot.