Do you want to compare Captain Boomerang with John Constantine? Discover the powers, weakness & weapons of Captain Boomerang and John Constantine from Captain Boomerang Biography and John Constantine Biography. Find out all about Captain Boomerang and John Constantine.# Check out how is Captain Boomerang unique and distinct from John Constantine. Discover their love interest, sidekicks, family tree and the movies and games list in which Captain Boomerang and John Constantine have appeared. Find out everything about them here!