When I spawn in a mob like an Evoker, get killed and re spawns they disappear from my game. But they are still there just invisible(but not with the invisibility effect). They still make noises, attack the player, etc. I haven't tested this out on all mobs, but I did notice it with the Panda, Evoker, and the Vex and neither of them appeared when I expected them too. They do not appear to have the invisibility effect because none of them show particles. Like I said, they act like they are still there by making sounds, attacking the player, etc.. While I am on the death screen, all of the mobs reappear again but disappear as soon as I re spawn.