A compulsion to reveal obscured parts of a map has been described to give a sense of exploring the unknown.[16] Crawford said that "reasonable" uses of fog of war, such as needing to send out scouts, "not only seem natural, but ... add to the realism and excitement of the game"[13] Merchant Prince displays over unexplored territory what Computer Gaming World described as a "renaissance-style map of dubious accuracy".[17] In some strategy games that make use of fog of war, enemy AI may have knowledge of the positions of all other units and buildings on the map regardless, to compensate for lack of true intelligence, which players may consider as cheating if discovered.[18] A designer may use fog of war to keep a game that has become impossible to win enjoyable, by hiding this fact from the player.[4]