Era is a type of Band. Explosion is a type of Band. Explosion is related to Flash. Flash is related to Spark. 
Theoretical is the opposite of Active. Active is related to Fit. Fit is similar to Acceptable. 
Era --IsA--> Band <--IsA-- Explosion <--RelatedTo--> Flash <--RelatedTo--> Spark 
Theoretical <--Antonym--> Active <--RelatedTo--> Fit <--SimilarTo--> Acceptable 