Ant-Man and the Wasp: Quantumania takes a lot of strides to set up Phase 5 of the Marvel Cinematic Universe and pull audiences further into its Multiverse Saga. The third installment of the Scott Lang portion of the franchise leaves San Francisco for the Quantum Realm, known as the microverse in the comics, opening the Avenger and his subatomic particle-obsessed colleagues up to diversions into other MCU narratives. The Easter eggs aren’t rampant in the Quantum Realm (though it necessitated not one, but two credits scenes), but the references are there if you are appropriately squinting:
The Blip Aftermath
Even after his demise, the actions of that troublesome Thanos (Josh Brolin) are still wreaking consequences on the world. Cassie Lang (Kathryn Newton) is arrested in the opening act of the film as part of a protest movement to stop the police from forcibly relocating those left houseless by the Blip. The crisis is an ongoing issue that we saw Aunt May (Marisa Tomei) address in Spider-Man: Far From Home and Spider-Man: No Way Home.
Jimmy Woo
FBI Agent Jimmy Woo (Randall Park), who was assigned to Scott Lang’s (Paul Rudd) parole case during Ant-Man and the Wasp, and played a key role in WandaVision, makes a quick cameo in Quantumania, having struck up a friendship with Scott, and taken up his hobby of close-up magic.
Veb
The creature made of ooze and obsessed with holes isn’t from the comics. But he is portrayed by David Dastmalchian, the popular character actor who previously portrayed Kurt, a member of Scott’s group of ex-con burglars, in the first and second Ant-Man movies.
Krylar
Bill Murray shows up as a former resistance fighter, Krylar, who has a long, and romantic, history with Janet van Dyne (Michelle Pfeiffer). A very minor comic book character, who was introduced in and died in The Incredible Hulk #156, Krylar was the leader of a group of assassins and mercenaries.
Chronopolis
Kang (Jonathan Majors) has built a city in the Quantum Realm, referred to as Chronopolis, which also serves as his residence in the comics. However, the comic book city exists outside of space and time in Limbo, and is guarded by the monster, Alioth, who we saw in Loki.
Stature
Cassie Lang has her own costume and access to Pym Particles. While shrinking combat takes some getting used to, she proves quite capable giant-sized. In her original comic appearances, Cassie preferred to grow rather than shrink and took on the name Stature as a member of the Young Avengers. This may be where her MCU future lies.
Incursions
The threat of incursions pops up in Quantumania, after getting their MCU introduction in Doctor Strange in the Multiverse of Madness. An incursion happens when the boundaries between two realities collide, resulting in the destruction of both universes. As Kang describes just before the final act, now that the sacred timeline has been leveled, the universes of the multiverse are colliding into one another.