Captain America's shield. It should be made of a mix of vibranium, adamantium, and the star material from Conan / Excalibur. And if this shield is ever destroyed, it is gone forever. They might be able to make a shield that has the same dimensions and weight from mostly the same materials, but it would always feel off to Steve.
Anyway. I should think of how the shield will go through time. After all, Steve can't be the only person to carry the shield. I feel like it should go:
- Captain America
- Winter Soldier
- Patriot (Elijah Bradley)
- American Dream (Shannon Carter Rogers)
- Danielle Cage
Something else that came to me is that I should look at how Crouching Tiger handles the Green Destiny. Perhaps one of these people, Patriot or Danielle Cage, has this upstart chip-on-their-shoulder and they basically take it and are like, "yep. It's mine now."
Actually, it being Patriot makes a lot of sense to me. I can see how Patriot would be like, "That was my granddad's and it should be mine, not yours" and he just takes it from Bucky. And perhaps Black Widow is like Michelle Yeoh's Yu Shu Lien and fights him for it. But ultimately, it needs to pass to the next generation. Although, unlike Yeoh and Yun-fat, Bucky and Natasha would get a happily ever after.
I should also think if there would be someone to give the shield to from the DC universe. I mean, I wouldn't want to do Nightwing or Green Arrow, but you could pick someone fun who's a very physical person.