Mod note:
Bow enchantet with Power III
and Power II
resp. Power I
and Power I
at the same time.
While playing in my survival world after a thunderstorm I was killing some Skeleton Traps and noticed on one of the bows dropped it was enchanted with Power 3, Power 2, and Unbreaking 2. I thought at first it said Punch 2 as one of the skeletons was knocking me back pretty far but then noticed it wasn't punch and that the bow had somehow been enchanted twice. I was able to recreate it by just spawning in more traps and using a looting 3 with Luck effect (if that does anything) with a high strength effect also so always one shot.
To recreate you can also give yourself a looting 100 sword. Although you will get a ton of bones and arrows you will be guaranteed to get a drop of armor and bow.
Code analysis by @unknown can be found in this comment.
Linked issues
is duplicated by 5
relates to 2
testing discovered 1
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Comments 14

Power III and Power II both on the same bow

Might only happen with naturally spawned Skeleton Traps, cannot confirm for Skeleton Traps spawned with commands in 16w02a

But is is still an issue in 16w02a for naturally spawned skeleton traps ?
Someone on reddit just reported having it happen to them: https://www.reddit.com/r/Minecraft/comments/4a3uzf/just_got_this_bow_from_a_skeleton_riding_a/
Add 1.15 to the versions, i had just gotten a power 2 power 2 bow lmao
So, could you get a infinity-mending bow via this method?
@unknown, no. Treasure enchantments (Mending, Frost Walker, Curse of Binding and Curse of Vanishing) are unavailable.
If you want Infinity and Mending, you have to go back to 1.9 to 1.11 (not 1.11.1)
I've tested this on an incredibly large amount skeleton traps and I was no longer able to reproduce this issue in 20w51a.

Was fixed in 20w30a along with MC-153195, however this report is not a duplicate because those were two separate bugs. This bug was fixed by adding net.minecraft.world.entity.animal.horse.SkeletonTrapGoal.disenchant(ItemStack)
which is called before the items are enchanted again.
What exactly is the bug here ?