Complex sentence: When Scorpius was invading the Magna Defender's home planet 3,000 years ago, among the monsters he brought with him are Radster, the frequently seen yet unnamed on-screen Blue Beetle monster, Fishface, Impostra, and Motor Mantis.
Split into simpler sentences: When Scorpius was invading the Magna Defender's home planet 3,000 years ago. Among the monsters he brought with him are Radster, the frequently seen yet unnamed on-screen Blue Beetle monster, Fishface, Impostra, and Motor Mantis.