Bug: The Rotation NBT is ignored when summoning armor stands since Minecraft Java 1.21.5.
How to reproduce:
Run: /summon armor_stand ~ ~ ~ {Rotation:[136.0f],NoGravity:1b}
Armor stand always spawns facing south (Rotation:[0.0f]), regardless of the value used.
Tested in 1.21.5 to 1.21.8 — same result.
In 1.21.4 and earlier, the armor stand correctly faces the given rotation.
Expected behavior:
The armor stand should appear rotated according to the NBT value.
Workaround:
Rotation can still be changed after summoning using:
/data merge entity @e[type=armor_stand,limit=1,sort=nearest] {Rotation:[136.0f]}
This indicates the NBT is valid but no longer applied during summon.
Environment:
Tested in singleplayer and vanilla server, no datapacks or mods.
Conclusion:
This is likely a regression introduced in 1.21.5. The Rotation NBT tag is silently ignored during /summon for armor stands.
Environment
single player without mod and datapack in 1.21.5 and above to 1.21.8
This is working as intended. As of 25w07a, the Rotation NBT needs to have two components (see MC-297634). An example of a correct command:
/summon armor_stand ~ ~ ~ {Rotation:[136.0f,0.0f],NoGravity:1b}