Avengers: Infinity War - 10 Characters Thanos Should Bring Back

6. Ultron

Previously...

Thwarted in his attempt to use Sokovia as a meteorite to wipe out all of humanity, Ultron was eventually defeated by Vision - who was supposed to be his own perfect creation - but not before killing Quicksilver.

And even in death, his legacy was cemented when the Sokovia Accords were drawn up.

Current Whereabouts

His surviving parts were sold on the black market, but he's very definitely dead (though how an artificial intelligence can "die" exactly remains a little murky).

Why He Needs To Come Back

Because he's a walking, talking reminder of Tony Stark's failures as well as the over-reaching that led to Quicksilver's death, superhero registration, Civil War, the death of hundreds in Africa and at the UN disaster and James Rhodes' paralysis.

If there's one "person" who could destabilise Tony most, it's Ultron.