The use of computers helped the filmmakers present their vision in new ways. The most notable use of computer animation is in the "wildebeest stampede" sequence. Several distinct wildebeest characters were created in a 3D computer program, multiplied into hundreds, cel shaded to look like drawn animation, and given randomized paths down a mountainside to simulate the real, unpredictable movement of a herd. Similar multiplication occurs in the "Be Prepared" musical number with identical marching hyenas.[12] Five specially trained animators and technicians spent more than two years creating the 2½ minute stampede sequence.[