Anyone Noticing That Whenever You Attack, Mobs Disappear?

So I was doing some quests where you had to kill for something, and the guy just kept on disappearing and then respawning afterwards. The damage I did was reset, making it impossible for me to kill the guy and complete the quest. Bug?
EDIT: NVM. I relogged and it worked

 

I've noticed this too, but it only happens on specific worlds. It still must be fixed at once though.

 

What server? We can fix it if you give the server number :)

 

Um... all of them?

 

It disappeared after relog, and this was right before the server I joined closed.

 

Salted is on it. Servers are being closed.

 

Ive noticed that when I use war scream as a warrior, sometime mobs will be thrown through a wall and just disappear. It won't go in the way, it just vanishes. It makes it very difficult to fight bosses as this sometimes happens when I use uppercut too

 

I actually got a bit spooked by this bug earlier today, I was in in the maro peaks mines looking for Baab, when I turned around and saw one of his followers look at me for a spit second and then vanish. Then suddenly all of the followers started appearing and disappearing at random, I got a little freaked out.