For the last week, it’s been ‘Ant-Man’ madness. There was the ant-sized teaser, the human-sized teaser trailer, and some new images from the upcoming Marvel film. And although we didn’t glimpse the villainous Yellowjacket in the trailer, we’ve seen some concept art and he looks pretty sharp. If you’ve been wanting to know more about Ant-Man’s foe, actor Corey Stoll has spilled some details on playing the villain and all the effects work that went into shrinking the stars down to ant-size.

Stoll plays Darren Cross in ‘Ant-Man,’ a former protege of Michael Douglas’ Dr. Hank Pym. In an interview with EW, Stoll explains Cross’ relationship with Pym, and how he came to make his own dangerous super-suit to become the villain Yellowjacket:

I was this child prodigy that Michael Douglas’ character Hank Pym discovered at an early age. He nurtured me and I was part of his technology company. I started to become aware of these rumors of this fabled technology that can shrink people to half an inch while keeping their full-size strength. And I became very obsessed with it and demanded that we move forward. But Pym had sort of buried it for ethical, moral reasons.

Now, I’ve discovered my own version of that technology and I’m using it for militaristic purposes. I’ve even started to use the technology myself, which has a sort of psychotic effect on people if they use it too much. I can’t get into the details of all the goodies of the Yellowjacket suit but it’s several generations advanced from what Ant-Man has. And then I put it on—and then I am Yellowjacket!

We also know that Evangeline Lilly plays Hope Van Dyne, Pym’s daughter who leaves the company to work for her father’s rival and former protege at Cross Industries. Cross and Paul Rudd’s Scott Lang aren’t the only ones utilizing this advanced technology to become super-powered—Van Dyne has a powerful, ass-kicking alter ego as well: Wasp.

With all these shrinking superheroes and villains, director Peyton Reed had to implement quite a bit of visual effects, some of which we spotted in the trailer as Rudd’s Lang shrinks down to Ant-Man size. Stoll explains some of that effects work and how they utilized motion-capture technology on set:

I did a bunch of motion-capture stuff, so that was completely abstract, without any set or even costumes. It’s just getting the movements and the facial performance. It almost feels like you’re making a silent movie, where the director shouts out, ‘And now you’re gonna get punched on the left side of your face!’ ‘And now there’s a swarm of ants!’ It was a lot of fun. The last time there was a movie about shrinking was like, Innerspace or Honey, I Shrunk the Kids. So there’s no comparison in terms of what the special effects can do.

There’s a whole unit that was dedicated just to macro photography and they had I think 45 days of shooting where every set, every prop, or anything that was part of the world that Ant-Man interacts with when he’s small, was shot with this crazy, next-level technology that enables you to film things at an incredibly small level without the distortion of a very wide lens. I think it will all add up to a believably immersive, super large-scale world.

Hopefully the next trailer for ‘Ant-Man’ will give us a taste of Stoll’s Yellowjacket in action. The full trailer is expected to arrive with the release of ‘Avengers: Age of Ultron’ on May 1. ‘Ant-Man’ also stars Michael Peña, Judy Greer, and Bobby Cannavale, and hits theaters on July 17.