After Thanos, Kang is one of the very biggest Avengers villains — and the time-travel shenanigans featured in Avengers: Endgame would be the perfect impetus to introduce the character in MCU Phase Four.
Kang has gone by many different identities in comics — even appearing as a hero named “Iron Lad,” at times.
Either way, that adds a major bit of intrigue to the next Ant-Man, a franchise that’s generally been treated as a series of comic sidebars to the main MCU.
It looks like it could be Kang the Conquerer, the time-traveling villain who has been a thorn in the side of Marvel Comics’ Avengers for decades.