So, i have my PvP Disc, 387ilvl, and i just wondered how easy it is to solo with, i was considering going to MC, but i know there are alot of dodgy magic effects there, and silences etc, ofcourse on my druid/warrior its pretty simple stuff, but wasn't sure about priest
MC is easily doable, regardless of spec of the priest. Of course as shadow, you can kill everything a lot quicker. Of course it's also beneficial if you have prior knowledge of which mobs in there have silencing, interrupt or stun mechanics, pull those separately. The rest you can just chain pull and holy nova/mind sear them down. Priest soloing is really underrated imo, even though the class itself is on the bottom half of the barrel when it comes to it.
MC's just faceroll. Shazzrah's a little annoying with silences etc, and some of the Fire Elemental trash have it too. For Ragnaros and Baron Geddon, make sure you have Levitate bound. The groups of Core Hound trash at Lucifron and Magmadar have to die within seconds of eachother, if you kill them one by one, they'll just respawn. Instead, just AoE down one pack at a time, and make sure the corpses have faded before pulling the next pack.
They're really the only things that can kill you in MC, and that's only if you're playing while half asleep.
The first boss in Blackwing Lair isn't soloable either btw, the mechanics make it impossible (although I think Hunters can do it with good pet control) since you have to use an Orb to MC the boss and make him destroy eggs placed around the room. During this, adds are spewing out attacking you (and therefore reducing the channel time of the MC) and the boss.
I actually found Onyxia harder then Alysrazor (havent tried Alys HC yet thanks to that I'm doing weekly raggy hc clears ;( And my alt priest can solo Normal alys but doubt hc)
Alysrazor is actually pretty easy once you get used to the routine. Even for heroic mode, it's pretty much the same routine, but it is more RNG dependent and higher DPS requirement. However personally I still find onyxia being easier than aly, mainly because aly has a longer fight length, which requires me to concentrate for longer.
When we were progressing in FL, our first H Aly kill came from me soloing from about 25%. Everyone died below so i stayed up, dispersed through her ability, and managed to get her down before she landed.