Hey there, I've been wanting to legitimately kill this guy for years now and finally made it a few months ago, but at the time, I didn't actually have anything to record it with - but now I do! I'd like to share my secret recipe to Dragonslaying, and here it is:
Weaponry: I used the 403 ilvl Gurthalak in this video, but if you have the Experimental Specimen Slicer I highly advice using this instead as a bad Gurthalak proc can and most likely will kill Razorgore at the worst possible time. (Talking from experience)
These are the buffs you want on yourself:
Seal of Righteousness - To clear out adds inbetween mind controls
Concentration Aura - This will allow you nearly 100% uptime on mind control, the only thing keeping you from 100% is the need to kill adds.
Righteous Fury - This will help a bunch in keeping aggro off Razorgore if used with Divine Storm (The healing will easily outthreat Razorgore).
Talents:
I used mostly the regular PvE Spec other than a few differences;
Last Word - This combined with Selfless Healer will help a lot in keeping both yourself and Razorgore alive long enough to finish the encounter.
Selfless Healer - Read above, should be obvious.
Divine Storm - This is in the regular PvE spec but I figured it was worth a mention anyway, as this is a very important talent.
Video:
Have a nice time killing that pesky dragonkin keeping you away from your Judgement set!
I'll add an armory link too:
Armory
Note: this should be taken with a grain of salt as I'm confident this encounter is easily done with less gear too.
Note no.2: I'm a terrible video editor, the music doesn't fit at all nor did I find any that did.