With the height of summer (and picnic season) upon us, what better way to celebrate than with an insane Ant-Man and billions of ants attacking the Avengers? Avengers #161 (1977) finds the team's resident headcase Hank Pym having yet another nervous breakdown/identity crisis, this time reverting to his original Ant-Man identity. Pym's mind also reverted back to a previous time frame, believing that the Avengers team has only recently come into being and that the people he sees in Avengers Mansion are either villains or impostors.
In a dynamic sequence illustrated by a young buck named George Perez, the addled Ant-Man launches a full-scale attack upon his perplexed teammates, culminating in a spectacular "growth-spurt knockout" of the Black Panther and the Beast (click on the panels for Pym Particle-like expansion).
SPECIAL BONUS BUTT-KICKING:
Of course, no Crazy Hank Pym story is complete without an appearance by his malevolent android "son" Ultron, who shows up seconds after Pym is subdued by the Avengers. Witness Ultron as he unleashes a KA-BLAAMM-flavored smackdown...