Among the Nimbanese species, a muhndee was a puzzle-solving competition, usually held between rival clans. Clan rivalries were a potent force in early Nimbanese history, but open warfare was unheard of. Instead, rival clans would present each other with a riddle, conundrum, or mathematical problem which had to be solved within one Nimbanese year (equivalent to 0.6 standard years). These allowed clan rivalries to die down into generally friendly competitions.