Jack Black whips some animal butt as the voice of Po, the rotund Dragon Master panda, in Jennifer Yuh’s Kung Fu sequel. A vengeful peacock, Shen (Gary Oldman), invents a contraption that “eats fire and breathes metal”---a cannon---to help him conquer China. Po, yearning to discover his past (his “father” is a goose, after all), is destined to obliterate Shen, though his attempts become a series of clumsy mishaps before he finds “inner peace” and saves the day. Animation at its best, this intricate 3D world (well worth the extra bucks) invites you into a land of legend, rolling hills dusted with fog and slapstick comedy. Besides the new director, the original writing team and all-star cast---including Angelina Jolie, Dustin Hoffman, Jackie Chan, Lucy Liu and Seth Rogen---remain unchanged.