All Monsters Attack (1969)

"A Godzilla father-son crisis: the furious new monster Gabara appears, taking aim at the throne of Monster Island!"

Ichiro Miki is a child living in the industrial district of Kawasaki, where his parents' constant struggle to make ends meet often leaves the schoolboy alone. Constantly teased by a bully nicknamed Gabara, his only friends are toy consultant Shinpei and fellow classmate Sachiko. Ichiro turns to escapist dreams of Monster Island where he befriends the equally bullied Minilla.