Take a look @ the origins of Marvel Comics' 'Giant-Man', plus an image of the newest vinyl doll and LEGO playset, confirming the superhero's appearance in Marvel Studios' "Captain America: Civil War":
"...the original 'Ant-Man', 'Henry Pym' could also reverse his shrinking capability to become 'Giant-Man'...
"...debuting as a 12-foot tall crime-fighter in Marvel Comics' "Tales to Astonish" #49 (Nov. 1963).
"Pym rejoined the 'Avengers' and adopted the new identity 'Goliath' in Avengers #28 (May 1966).
"Giant-Man also appeared as a supporting character in Marvel's 'Avengers Academy' from issue #1 (Aug. 2010) through its final issue #39 (Jan. 2013).
Take a look @ a new "Captain America: Civil War" LEGO playset with 'Giant-Man' in his 'Ant-Man' outfit.
Click the images to enlarge...