There is a bucket for one in creative. I looked at the discord and found "It's bug on one of the versions that it's an issue with the modloader I believe" but I don't really know what this means. Like it is a NeoForge issue?

So based on my testing this isn't actually around picking it up, Can you enable Hitboxes and try again and see if it works as it does on my side, the ManOWar hitboxes are really rough and I have to fix in the future but I want to verify this is the case for you @Verse-V

Only Baby ManOWars can be picked up in buckets, did you verify the one you tried to pick up is a baby?

I tried a baby Man O War just now, albeit in Fabric this time 1.21.1. It would not let me pick it up. I tried for a while in water, first in shallows and then deep water. I then put one on land and still could not bucket them.

https://i.imgur.com/HtffY0y.png

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