The phrase "went over the hill" typically refers to someone who left or disappeared without notice or explanation. Antonyms for this phrase might include "arrived," which indicates an intentional and expected entrance; "reappeared," which suggests a return after being absent; or "remained," which indicates someone has stayed in one place. Other antonyms might include "stayed put," "stuck around," "showed up," or "stayed behind." These antonyms all suggest a sense of stability, reliability, or predictability, which is the opposite of the unpredictability and mystery associated with "going over the hill.