There was a feature in Call of Duty Zombies games such as Call of Duty Black Ops 3 and this feature was being able to keep last zombie alive in order to explore the map, take a break while playing on co-op and get ready for next round before current one ends. But in Black Ops 4 this feature is not there and players can not keep the last zombie alive as it dies in 5 to 10 minutes. Lack of this feature makes it so hard to play and enjoy the game. A lot of players suffer from this issue and if we can solve it everybody will be happy.