Although these ideas were explored with concept art and movement tests, the final look and feel of the Quantum Realm was simplified. The Realm remained somewhat of a psychedelic place, almost like a mood ring, and subtly ebbed and flowed to interact with the characters inside it.
"Everything was moving," says Hellen. "Everything was an effects simulation. We had multiple different layers to those effects simulations to give us different types of effects. We had large crystalline-type spikes that were coming up out of the ground, as well as negative height fields, which were areas that were eating away down into the ground and had a refractive, glassy kind of quality to them with underneath lighting."
Before the characters reach the Quantum Realm, however, they journey via a specially made pod through a series of microscopic places. Some of these were realized by other visual effects vendors, while Method Studios also worked on the journey shots, including those that zoom past what appear to be giant worms. These are actually tardigrades, which in real life are between a millimeter and a tenth of a millimeter long.