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Marvel characters such as Black Widow, Wolverine, X-23 & even more recent & unique additions like the Stepford Cuckoos & Fantomex all owe their existence to Captain America & the concept of the super soldier serum. Such infamous places as the Red Room & storylines like Weapon Plus, also can trace their roots back to the super soldier project. This is a very good article worth reading.
CAPTAIN AMERICA'S Legacy: How Super Soldier Serum Fuels Past, Present, Future Marvel Universe | Newsarama.com
CAPTAIN AMERICA'S Legacy: How Super Soldier Serum Fuels Past, Present, Future Marvel Universe | Newsarama.com