Because Fox owns the rights to the "X-Men", it could use either the 'Scarlet Witch' and 'Quicksilver' in an "X-Men" movie or spin-off.
But Feige also confirmed that Marvel Studios could also use the same characters in an "Avengers" movie.
'The Scarlet Witch' (aka 'Wanda Maximoff'), created by Stan Lee and Jack Kirby, first appeared in Marvel Comics' "X-Men" #4 (March 1964). She is the daughter of 'Magneto', the twin sister of 'Quicksilver' and the paternal half-sister of 'Polaris'.
The Scarlet Witch has featured in four decades of Marvel continuity, starring in two self-titled limited series with husband the 'Vision' and as a regular team member in superhero title the "Avengers".
The character has also appeared in other Marvel-endorsed products such as animated films, arcade and video games, television series and merchandise, including action figures and trading cards.
The Scarlet Witch is a mutant with the ability to manipulate probability via her 'hexes', often manifesting physically as 'hex spheres' or 'hex bolts'.
She can use her hexes to light flammable objects, contain or remove air from a particular volume, deflect objects, stop the momentum of projectiles, open doors, explode objects, create force fields and deflect magical attacks.
'Quicksilver' (aka 'Pietro Maximoff'), first appeared in Marvel Comics "X-Men" #4 (March 1964), also created by Lee and Kirby. He is the son of Magneto, the twin brother of the Scarlet Witch, and the paternal half-brother of Polaris.
Quicksilver is a mutant capable of moving and thinking at superhuman speeds. Originally capable of running at the speed of sound, exposure to the 'High Evolutionary'- designed 'Isotope E' made it possible for the character to run at supersonic speeds up to Mach 5, while resisting the effects of friction, reduced oxygen and kinetic impact.
Quicksilver's speed also allows him to perform fantastic feats including the creation of cyclone-strength winds, the ability to run up the sides of walls and crossing bodies of water.
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