WIKI

Lottery Spawn

A Lottery Spawn means that after a period of time has passed since a Notorious Monster was slain, there is a chance that killing its Place Holder(s) will trigger the Notorious Monster to spawn again. On standard Lottery Spawn conditions, there is no guarantee that the Notorious Monster will ever spawn after a certain period of time. With each slaying of its Place Holder, you have a chance to spawn the Notorious Monster after a set minimum amount of time has passed.