I am working on a project where I must make an ultimate Skyblock map in Minecraft. I am using commands to generate mobs like cows and zombies. However, with the current despawn time in Minecraft, they fill up their islands and lag the game quite badly.

Here is an example of what I am doing now: /summon creeper ~ ~ ~ {Age:5900}.

This creeper should despawn after only 5 seconds, but it persists.

My version is 1.17.

  • Can you confirm if you are always using the value {Age:5900}? That seems like a very high value for 5 seconds.
    – user228576
    Jun 12, 2021 at 13:25
  • Yes. It was supposed to DESPAWN after 5 seconds. Mobs despawn after 6000 ticks and 1 tick is 0.05 seconds.
    – Elliott T
    Jun 12, 2021 at 22:10
  • I also encountered the bizarre problem that this works for dropped items as well.
    – Elliott T
    Jun 12, 2021 at 22:18

2 Answers 2


For a 5 second lifetime, you need to use the command:

summon creeper ~ ~ ~ {Age:100}

You can always use scoreboards.

First type in chat:

/scoreboard objectives add Death air

Add an always active repeating command block with

/scoreboard players add @e[tag=“Death”] Age 1

Then add another always active repeating command block with /kill @e[scores={Age=20}]

(Note 20 ticks is one second, and since the repeating command block is basically reactivating every tick, each mob will be given their own 1 point every tick, and once they reach 20, that means they’ve been existing for one second.

You’re of course free to change 20 to any amount of seconds such as if you want 6, you just multiply 6 • 20. Also note that you have to summon mobs with tags as well as unlike despawning, the items drop.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .