When something hurts you and it is not a witch and you use the /effect give playername minecraft:instant_damage 1 3 command, it shows bugged death message. (death.attack.magic.player instead of player was killed by magic whilst trying to escape mob)
Note: Also works in 1.14, 1.14.1, 1.14.2, 1.14.3 and all of their pre-releases.
Thank you for your report!
We're actually already tracking this issue in MC-133088, so I resolved and linked this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
If you haven't already, you might like to make use of the search feature in the future to see if the issue has already been reported.
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