Over the years, Mjolnir has been shown to have some very strange abilities. One of the most unexpected and peculiar though was the reveal that it could summon those from the dead who had sworn an oath over it (it's hard to say when exactly Captain America did this, but it was presumably during one of the occasions he was able to wield the hammer). This led to the recently resurrected Thor and Steve Rogers having a touching conversation about their friendship and whether Cap wanted revenge on those who had slain him. Of course, it was later revealed that he wasn't really dead, so just who the hell was Thor talking to?!