Some of the greatest superheroes of all time have heeded the call of “Avengers Assemble!” Also, a lot of randos.
Marvel
Dr. Druid
So how do you get to be the worst Avenger? Dr. Druid — Dr. Anthony Ludgate Druid — was a psychiatrist (an occupation largely centered around sitting and talking), who got trained by an ancient mystic to be the backup sorcerer if anything happened to the more popular Doctor Strange. Besides being a literal superhero understudy, he also got mind-controlled by a villain named "Terminatrix," left the team in disgrace, joined another team, got mind-controlled again, faked his own death, betrayed at least one more team, and then bravely got killed for real.
Marvel
Jack of Hearts
Jack of Hearts is a half-alien whose scientist father exposed him to experimental "zero fluid," giving him the power to shoot energy blasts. He chose a playing-card-themed identity for unclear reasons and hung out in space for a while, before joining the Avengers during an emergency hiring crisis, and eventually blew himself up in space — along with a child murderer he grabbed on the way. Classic super heroics.
Marvel
Triathlon
This dude is a disgraced Olypmic athlete who got his powers from a weird cult that subsequently pushed the Avengers to bring him on as a diversity hire as part of a secret plot to infiltrate the team. Very questionable. He later becomes the 3-D Man, maybe because he didn't feel dorky enough.
Marvel
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