Mtg Zur the enchanter rules.?

Hey I was just wondering a few things when using Zur the enchanter. If I attack with Him am I able to grab Erayo's essence? I don't really think I can but just wondering. Also can I put other enchantments onto Zur himself even if he's already enchanted with Diplomatic immunity? I heard that you can because something about zur's ability doesn't target anyway can someone clear this up for me?