I would love to see returning characters. This season is a climactic one; the writers are teasing the return of all the popular heroes, villains, and background characters - pirates, Vikings, Huguenots, General Grant’s army, the Pilgrims, Baroque artists, Rococo artists, Romantic artists, those who marched on Washington, Winged Hussars, Winter War soldiers, Incas, the Vietnam veterans, the Vietnam protestors, Soviet snipers, the IRA, Jacobins, Francoists, Carthaginian emperors, the Sons of Liberty, Enlightenment philosophers, the victims of Wounded Knee, the Mafia, Royalists, Parliamentarians, the 300 at Thermopylae, the Underground Railroad people, Nubians, the Black Hand, Islamic Golden Age scholars, Old West outlaws, Philippine revolutionaries, samurai, American pioneers, the National Organization of Women, Magellan's crew, Dutch traders, those who suffered the Irish famine, Gestapo, Bolivarians, trade unionists, Romani, the Continental Congress, Quebec revolutionaries, soldiers at the Alamo, Hussites, Titoists, Belgians Congo leaders, Brazilian monarchs, Cossacks, ancient Olympic athletes, Gilded Age tycoons, Pan-Africanists, Luther's supporters, Battle of Trafalgar soldiers, Polynesian sailors, Colombian drug gangs, the Kievan Rus', the Ottomans who took Constantinople, Alexander the Great's army, those who marched on Washington, Phoenician sailors, Idi Amin's government, trench soldiers, flappers, Romanovs, Portuguese spice merchants, transcendentalists, stadholders, the Huns, The 588th Night Bomber Regiment, Etruscans, Haitian Revolution uprisers, Moors, the Goths who sacked Rome, Norman invaders, the Apache, Black Death victims, D-Day veterans, the Roughriders, Great Zimbabwe architects, Maurya emperors, neanderthals, Yorkists, Lancastrians, the Knights Templar, Caesar's assassins, Danes who took Schleswig-Holstein, the Tamil Kings, Risorgimento Red Shirts, Maoists, Bleeding Kansas militia, Scottish clansmen, Jesuits, the British East India Company, Ataturk's soldiers, the Popes who sold indulgences, Boxer Rebellion participants, the Medici, Canadian fur trappers, people whose heads were chopped off by Robespierre, the African National Congress, greasers, Frederick the Great's army, Armenian Genocide victims, prisoners sent to Australia, destroyers of the Berlin Wall, Pancho Villa's gang, Nigerian freedom fighters, Abbasid caliphs, Jamestown colonists, Zulu warriors, Captain Cook's sailors, Forrest Gump, Three Kingdoms-era warlords, Gandhi's supporters, the Spanish Armada, Peronists, hippies, Freemasons, Prohibitionists, Federalists, Anti-Federalists, Aztec leaders, Hutu supremacists, the Sea People who caused the Bronze Age collapse, the Kuomintang, Ba'athists, Glorious Revolution leaders, more Vikings, the Khmer Rouge, the American Colonization Society, Achaemenid emperors, beatniks, Mongol hordes, Trotskyists, residential school members, Italo-Ethiopian War veterans, Seneca Falls suffragettes, Zionists, the Bonus Army, witches who were burned, Stonewall protestors, existentialists, Green Mountain boys, Burgundians, Tammany Hall members, victims of the Trail of Tears, Knights of Labor, passengers on the Lusitania, 49ers... it's all been leading up to this massive crossover event.