f you’ve seen The Twilight Saga: Eclipse, odds are you left raving about the wolves — particularly the scene in which Jacob, in wolf form, saddles up to Bella during the training sequence. It’s one of the moments Phil Tippett — a two-time Oscar winner for Jurassic Park and Return of the Jedi whose visual effects house, Tippett Studio, handled the wolves for both Eclipse and New Moon — is most proud of. “That was an unusual thing for us in that most of the time, we are doing these ‘god awful animals start tearing each other apart,’” Tippett told us recently, phoning from England where he’d just celebrated Ray Harryhausen’s 90th birthday. “So it was great to have a quiet moment. A tender scene that telegraphs a budding and suppressed relationship was tricky. In fact, the entire training sequence was difficult in that the wolves do nothing. A bunch of wolves standing around watching vampires train and trying to portend some kind of anxiety was tricky. It’s tricky for any actor when you have to carry a certain part of the scene where you do nothing, because you have to figure out a way of filling up the nothing with something.”

It was important to Eclipse director David Slade that Taylor Lautner actually film that scene with Kristen Stewart so she was able to establish eye contact with him instead of with a golf ball that could’ve been used as an eyeline and painted out later. The wardrobe department dressed Lautner in a neutral grey leotard and hoodie — primarily so his skin tone wouldn’t bounce back onto Stewart and create lighting issues when Wolf Jacob was added, Tippett says. We, however, like to believe someone was already thinking about the DVD extras. That will be great, won’t it?

The tender moment was made more challenging by the fact that Slade had a different vision of the wolves than New Moon director Chris Weitz. For starters, Weitz wanted the wolves to have their actor’s eyes. “He kind of wanted the performance to feel like the wolf behavior was being filtered through a human brain,” Tippett says. Slade wanted the wolves to have wolf eyes to de-anthropomorphize them. “David wanted the performances to be more feral, twitchy, and agitated. He wanted to see wolves that were more photographically representational, which had to do with things like getting more hair follicles, making the paws smaller.”

The believability of the wolves was equally crucial in the climactic fight sequence with the newborn vampire army. “We had to come up with a rationale for what happens when a 1,300-pound wolf that’s running 35 miles an hour crashes into a newborn vampire [played by an actor that weighs 165 lbs], how we justify that,” Tippett says. “David allowed us the transgression of saying, ‘Well, let’s just say that the newborns, since they’re not made of human material but some kind of a more marble-like material, have an actual mass of something like 500 pounds, so they have a lower center of gravity.’ And that allowed us to begin thinking about how to make all of that palpable, without thinking that they’re existing in two different physical universes.” Watch a clip of how that action gets put together below.

Which wolves did you prefer: New Moon‘s or Eclipse‘s?