Editors Notes: This is an theory article based on the current information we have. We don't have any inside information.
Now last week both Latino-Review and HitFix revealed that a prologue villain named Baron Von Strucker is scheduled to make an appearance in The Avengers: Age of Ultron. They also revealed that Quicksilver and Scarlet Witch will be working with the Baron in the prologue which would have the super powered duo come in contact with The Avengers. The websites didn't know if they were simply working for HYDRA or captured by HYDRA.
As most of you know by now Quicksilver and Scarlet Witch are the only characters both FOX and Marvel Studios may use in their separate films. The handicap that Marvel has is that Quicksilver and Scarlet Witch may only be called Pietro and Wanda Maximoff. They also may not use the duo's back story of being the children of Magneto or be called 'Mutants'.
Now a new theory has emerged on why Marvel is specifically using Baron Von Strucker with Quicksilver and Scarlet Witch. Marvel Studios maybe using the HYDRA villain Baron Von Strucker as Marvel Studios 'Magneto'. According to the comics Baron Von Strucker also had two super powered children named Andrea and Andreas Von Strucker. Since Marvel have to make up an original origin for the Maximoff Twins it seems that they may go the route and make them the film version of Andrea and Andreas Von Strucker. Don't worry they will still have their speed and magic super powers but this way they will still be the children of a super villain...which was the one thing that they would miss not being the children of Magneto.
Of course this is all a simple theory but it would make complete sense.
The Avengers: Age of Ultron hits Summer 2015
