Hank Pym

Henry Jonathan "Hank" Pym was the first Ant-Man and a major character of the Marvel Cinematic Universe. He is the deuteragonist of the 2015 Marvel film Ant-Man, the tritagonist of its 2018 sequel, Ant-Man and the Wasp, and a minor character of Avengers: Endgame. 
He is a brilliant scientist who managed to create quantum particles that allowed him to shrink in size, and later became a consultant for S.H.I.E.L.D. and partner of Wasp. Decades later, Hank decided to have Scott Lang become the new Ant-Man, and help him stop his former protégé, Darren Cross, from using the same particles to sell across the world. Hank would later work on trying to find his wife, Janet, in the quantum realm after Scott managed to return from it when defeating Darren. He would succeed in finding Janet, and was later killed by the Mad Titan Thanos during the hunt for the Infinity Stones. He was resurrected by the Hulk in 2023, and later attended Tony Starks' funeral to honor his sacrifice in stopping Thanos and his army.
He is portrayed by famous actor Michael Douglas.