appending to previous comment: I don't know if this matters, but I had just repaired the enchanted trident in question on an anvil by merging it with a mostly repaired non-enchanted trident. The resulting trident appeared to be what you would expect from this repair, but disappeared upon first use upon a drowned at point blank range.
appending to previous comment: I don't know if this matters, but I had just repaired the enchanted trident in question on an anvil by merging it with a mostly repaired non-enchanted trident. The resulting trident appeared to be what you would expect from this repair, but disappeared upon first use upon a drowned at point blank range.