20 Biggest Wasted Opportunities In The MCU

9. Quicksilver

You didn't see this coming? Well, perhaps you should have. 

Introduced in the post-credit scene of Captain America: The Winter Soldier and offered a more prominent role in Avengers: Age of Ultron, Pietro Maximoff, aka Quicksilver (Aaron Taylor-Johnson), is portrayed as the caring brother of Wanda Maximoff (Elizabeth Olsen), the pair of their grieving orphans with a personal grudge against Tony Stark.

Charming and well-performed, Quicksilver wastes little time forming relationships with the Avengers throughout his feature debut, particularly Hawkeye (Jeremy Renner), and he seems set up to make a strong addition to the team alongside his sister. 

Until, that is, he's killed in Age of Ultron's climactic battle, and seldom mentioned again. Now, he feels like little more than a narrative trope to advance his sister's story - hers a tale of grief and loss - rather than a real character, one that showed tremendous promise only to be tossed aside for shock value.