My friend and i have been investigating this bug for a few months now and have worked on a video that puts all the knowledge we have about it.Everything is in the video, but briefly,there is a bug related to this trait that has been known for quite some time now. Said bug is whenever a phantasm fails to complete its full attack sequence for no apparent reason, simply put. Say I use the skill sequence phantasmal swordsman, into signet of ether, into phantasmal swordsman again. I would spawn two phantasms from each cast of phantasmal swordsman, and each one would resummon itself once upon death, for a total a four phantasms. If I were to get bugged, one of these would become a clone before attacking, effectively giving me three phantasms instead of the expected four.