If you get killed by an ender dragon's acid on the ground, it will just give the name entity.AreaEffectCloud.name instead of a real name.
Linked issues
Comments 2
Dupe of MC-68446
MC-87031
Being killed by ender dragon's acid gives "entity.AreaEffectCloud.name" as killer
Resolved
Duplicate
0
qwerty23495
(Unassigned)
Unconfirmed
Minecraft 15w34d
Retrieved
The entity.AreaEffectCloud is the real entity that killed you, as it applies instant damage to you. But it could be named "Ender Dragon".