[1.7.10] Crash with Zelda Sword Skills

[Shahelion]

Was wearing the lesser ring of splinching, and it worked fine for a good IRL week or two, then suddenly this happens. Was a Random Things blood moon at the time, although by far not the first...nothing about this situation hadn't happened before without issue. Those Wizzrobes were my primary source of ender pearls.

https://gist.github.com/Zsashas/c2036778cffcf3ab97386a6a9b07fb7f

[Tuhljin]

The crash appears to be caused by a problem with EntityWizzrobe (zeldaswordskills). The only thing Automagy is doing at its latest point in the log is using the standard method for trying to damage an entity - and I've double-checked that so it should not be passing null. The crash occurs several steps beyond that point.

[Shahelion]

Apparently there's a null item stack involved in drops.