snipe hunt

/S N AY1 P AH0 N T/
noun
  1. 1

    A prank in which a gullible victim is sent off on a fruitless search for a nonexistent item.

verb
  1. 1

    To participate, as the gullible victim, in a snipe hunt.

Source: https://en.wiktionary.org/wiki/snipe%20hunt