Complex sentence: Asgard is the name of a fictional realm and its capital city within the Marvel Comics universe based on the Asgard of Norse mythology and is home to the Asgardians and other beings of Norse mythology.
Split into simpler sentences: Asgard is the name of a fictional realm and its capital city within the Marvel Comics universe. Based on the realm of the same name from Norse mythology, Asgard is home to the Asgardians and other beings adapted from Norse mythology.