“To fight monsters, we created monsters” – so goes the tagline for Guillermo del Toro’s summer tentpole for Warner Bros. A new 4-minute Pacific Rim featurette gives viewers a look inside the massive robots deployed to battle the kaijus that have emerged from the sea in the near future. “Every movie has to have a portion of analog practical effects to really convey the sense of physical reality of the film,” del Toro says, then he details how they did it. Stars Idris Elba and Charlie Hunnam describe the challenges as they endured del Toro’s “torture machine.” Suffice it to say, this ain’t Godzilla vs. Mothra. The Legendary Pictures actioner opens July 12: