Yi was originally a type of divine beast, but one should not forget that in the legends, it was also famous for its warlike nature. Most importantly, it was also inextricably linked to the leader of the zombies.
That was why the kun itself had a trace of evil attributes. It was because of this that a divine beast like the kun was more easily affected by some negative energy.
The kun's corpse under the devil World had been affected by the negative emotions, which was why it had become like this. If it was given some time, it might become a corpse puppet, an existence like a general.
