"Weapons for War Machine and Hammer drones were based on real modern weapons and ILM created style sheets, particularly since the drones were associated with a branch of the services," Snow suggests. "The Naval drones had mounted missiles similar to what you'd find on battleships; and the Air Force drones, they'd be based on a sidewinder missile. The looks of the suits were based on the branch of service as well. For the Air Force drone, they went with an F22 stealth paint look that's completely non-reflective and allows the plane to not be radar-detected. But it was so well camouflaged that you couldn't see it in shots. So we had to go back and actually dumb-down the materials just a bit and made it more reflective than you actually want if you're trying to hide your Air Force drones. The signatures of the weapons -- the muzzle flashes, tracers and the look of explosions -- were a challenge, too."

Meanwhile, Marc Chu, the animation supervisor at ILM, was tasked with better performances. "We couldn't really see their faces, so [we] worked on making their fighting styles very distinctive and making them act like different characters," Chu says. "Iron Man (who's refined in a completely new suit and has more over-the-top weapons) was the most nimble and flexible of the group whereas War Machine was more brute force. And with Whiplash, we wanted to emphasize the whips and did a lot reference for that. We really wanted to go for a samurai-like feel, reusing drone armor [for the final battle]."

ILM made full use of Imocap this time. "It's tough to meld a performance of Robert with a CG suit and make it look natural, especially when there is such a big height difference between the suits and the actors," Chu continues. "And in some cases, Jon wanted to change some of the nuance of performance as well with a hand gesture. Well, Robert is very animated, so sometimes we wanted to tone that down a tiny bit. This gave us that flexibility."

Apparently Whiplash's hand-crafted suit for the final battle was a last minute addition that required 60 new shots to raise the stakes. "It was recognized early enough to make the adjustment," Chu explains. "We utilized the Lidar set of the Japanese Garden, which was shot in LA and we used our own [Imocap] system to postvis the end battle. We had gotten a previs movie from everyone down south (Genndy Tartakovsky designed the Stark Expo chase sequence and prevised the original version of the Japanese Garden battle) and utilized background plates, virtual cameras and used our animators as Imocap standins for Iron Man, War Machine and Whiplash. This enabled us to feel part of the choreography."

Again, this was another instance of ILM's creative input and keeping it real world with director Favreau's demands. And look for the new lighting toolset to be used from here on out at the studio.

Bill Desowitz is senior editor of AWN & VFXWorld.