EVANSTON—Northwestern University officials announced in a statement Sunday night that one Prius in the school’s SafeRide fleet is actually a Transformer in disguise hiding from the evil lord Megatron. The Transformer, Tigerzord, was hiding on Earth after fleeing Cybertron, its home planet. Tigerzord failed to steal the mighty Allspark from Megatron, and thus was forced into hiding to avoid the wrathful robot’s ruthless minions Starscream, Bonecrusher, Frenzy and Brawl. Tigerzord was discovered when it mistakenly transformed while carrying several sorority