I can't see my mobs!

Hi all,

I just switched to Spigot on my server and that all went fine. But when I went to spawn in a MythicMob I couldn't see it. After playing around with it I realized I can't see or hear my mobs but they can still damage me, so I know they're there. I'm using the latest build 4.0.0 (I think that's the number for it.)

Any help is appreciated! Thank you!