You Nitwit! Heroes are Extinct!!

An alien hero from a distant star arrives on Earth, eager to test his might against the planet’s legendary superheroes. There is just one problem: Earth has no actual superheroes. Having grown up watching Japanese tokusatsu series like Power Rangers and Ultraman, the extraterrestrial warrior mistakenly believes these fictional characters are real. Determined to prove his strength, he assembles an invasion force on his home world and launches an assault on Earth as the ultimate trial of power. However, when the invasion begins, not a single defender appears to stop him. Now, the bewildered alien commander is left stranded with an entire army and absolutely no one to fight.