What Marvel antihero gained powers through military experiments and is known for his distinctive red facial markings?

Red Skull

Which sailor hero spent ten years journeying home to Ithaca after the Trojan War? Which South American country traditionally launches fireworks at midnight on Christmas? What part of the plant captures sunlight energy for photosynthesis? What was the widely used textbook promoting American spelling and language in the 19th century? In mythology, who turned everything he touched into gold?