Tales to Astonish (1959) 27-A

"The Man in the Ant Hill!"

Henry Pym is a brilliant scientist. He has developed a series of formulas, one that reduces objects in size, another that reverses the effect. The scientific community scoffs at his ideas, so he ultimately experiments on himself. When the formula is more effective than he imagined, he is reduced to ant size, and finds that he cannot reach the restorative formula. Worse yet, he has attracted the attention of the backyard ants and ends up on the most bizarre adventure of his life.

1st appearance of Henry Pym, later Ant Man.
1st superhero treatment by Marvel Comics.

"Trouble Bubble"

"Mirror, Mirror, On the Wall"