One if the fitst skulls I remember seeing and loving ♥ Drew this for an art class, so know it well. Iron Maiden "Killers" just a cool concept that they carried throughout their long career.
Iron Maiden - Aces High, single from Powerslave
Iron Maiden - 2000 - Brave New World
Iron Maiden: The Number of the Beast Album Cover Parodies. A list of all the groups that have released album covers that look like the Iron Maiden The Number of the Beast album.