I need help with modifying the players velocity in Minecraft.

I have tried:

/data merge entity Bla0 {Motion:[0.0, 0.8, 0.0]}


/data modify entity Bla0 Motion[0] set value 0.001d

but both give the error message:

Unable to modify player data.

I run minecraft 1.18.2 with optifine. The server is on paper with no plugins.

  • Um, speed potions?
    – aytimothy
    Mar 5, 2022 at 7:23
  • @aytimothy speed potions do not give players velocity. They increase a players maximum speed.
    – Topcode
    Mar 5, 2022 at 14:03

1 Answer 1


I'm pretty sure the answer is you cannot. Certain types of data are unable to be modified like that, and it is considered "works as intended" by Mojang. Basically, certain types of data are static, so to alter them would require the player to rejoin the world. Their solution was to just make them unable to be modified.

You can read more about it here: https://bugs.mojang.com/browse/MC-122102

You must log in to answer this question.

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