Hank Pym, also known as Yellowjacket, is the main antagonist of "What if.... the World Lost its Mightiest Heroes?", the third episode of the Marvel animated anthology series What if... He is the inventor of size changing "Pym Particles" and a former superhero working for S.H.I.E.LD, as Ant-Man. However, after the death of his wife and daughter, he became disgruntled against Nick Fury, and decided to take revenge on him by killing every potential member for his "Avengers Initiative".

Tier: 9-A

Classification: Human, Scientist

Powers and Abilities: Superhuman physical characteristics, genius intelligence, martial arts, stealth mastery, size manipulation(Of himself and others via Particles Discs), flight, energy projection and heat manipulation with Energy Stingers

Attack Potency: Small Building level(Would be just as strong as the canonical Yellowjacket), higher when shrunken(Like Scott, Hank could easily kill regular humans if he's not using restraint. Killed his Black Widow), can negate durability via shrinking into the opponent's body or using Pym Particles Discs on the opponent's internal organs

Speed: Athletic Human travel speed with Massively Hypersonic+ combat and reaction speed(Comparable to Black Widow)

Lifting Strength: Athletic Human, Superhuman when shrunken(Threw Black Widow around a room)

Striking Strength: Small Building level, higher when shrunken

Durability: Small Building level (Took casual slaps from Loki and getting punched into a gravestone by him)

Stamina: Superhuman

Range: Standard Melee Range, Several Meters with energy pulse stingers

Standard Equipment:

•Yellowjacket Suit: Suit manipulates wearer's size and can shoot energy blasts via its stingers.

•Pym Particles Discs: About the size of a coin and shaped like a triskelion styled shuriken, the dics are filled with specified forms of Pym Particles. Targets impacted by Red Discs shrinks to the size of an insect. Targets impacted by Blue Discs enlarge to a bigger size.

Intelligence: Extraordinary Genius(Created the Ant-Man suit and Pym Particles. Under S.H.I.E.LD's nose, used their own candidate list for the Avengers Initiative against them by assassinating every potential member of the group, including the Hulk, who is vastly more powerful than Hank himself. Is stated to be one of the smartest people in the MCU)

Weakness: Became mentally unstable after the death of his daughter, Hope.