/summon ArmorStand ~ ~ ~ {UUIDLeast:1000000000000000000L,UUIDMost:1000000000000000001L,}
/entitydata @e {UUIDLeast:1000000000000000000L,UUIDMost:1000000000000000001L,}
/kill @e[type=!Player]
Found ArmorStand
That entity cannot be found
Comments 3
That "bug" even makes sense. Minecraft stores every entity based on its UUID. Take this example:
You have a vocabulary box and you have two cards in it, both with the same word to translate. You would be confused because you expected all other translations for this word to be on one card. The same way Minecraft is "confused" when you say this entity has this attributes but has at the same times some other attributes which are totally different
Duplicates MC-44904
That's to be expected.
Simply don't summon two equal UUIDs.