NPC's don't spawn properly

[darkdiplomat]

Changes to logic in Minecraft 1.8 have caused the current NPC system to no longer function.
Possible fix may require using a EntityPlayerMP extension and using the V2 UUID system

[tylerhoot]

I can agree some of the creatures will not spawn which are on the normal creature list i.e. the silver fish via spawn eggs

[gerardvanschip]

Just tested this and they do spawn yet invisible. Just make a 2x2x2 hole, spawn several in there and poor water in, you will see splashes and hear them dying.