I have for you a story, and then a question. First the story:
So, this 5.2 PvP season kicks off and I jump into arenas with much enthusiasm. I am a DISC priest in all last seasons conquest gear (with weapon) and running 2v2 with a Hunter with same level of gear. We had good fun... we win some, lose some and all's fair in love and war. For most matches if we lost, we could see how we were bet, or how we could have done something better - nothing seemed OP. We then hit a couple different teams that sported a resto Druid, and well the druid would NEVER run out of mana.
The first team we ran into was a Frost DK and Resto Druid. The DK stuck on me most the time, and my Hunter team mate stuck on their Resto Druid 100% of the time. You see, the DK really hit like a wet blanket, and so I could easily keep me alive. Sure my mana went down slowly, but I would manage through trickery to get away and drink (i.e. a good fear, run away and the DK would usually switch to my partner because I was so far away. At this point I would drink). So yes, my mana was going up and down as I managed to drink. HOWEVER, the druid, with the hunter on him + hunter pet never drank once. Yet, the druids mana was solid. Never below 90%.
Through subsequent matches against resto druids (we saw two different teams with restodruids that night, but ran into them a few times each) we tried different techniques; 1) attack the DK 100% then switch to the druid when he comes out of hiding 2) Me keeping on the druid, fearing him out from pillars as much as possible, 3) both of us attacking the druid 4)... other things I can't think of for now..
But through out all the matches, we could not drop their mana.
So the question is: Is it now just a fact that restoDruids have massive regen now that is impossible to get down their mana? or Is this the first sob-story you have heard of, and RestoDruids Mana regen is no different and we need to LTP? Or is there something new with 5.2 RestoDruids we need to consider?
We never ran into this last season, that is why I am quite baffled.
That's just 2v2 life for you. Priests don't really play outlasting games, you just can't compete with the other healers (Excepting maybe Monks, I'm less sure about them) in terms of efficiency and regen. You need to try and end matches before mana becomes an issue by coordinating long CC chains with your partners, offensively purging targets to set up kills, and bursting with your partner (Shadowfiend, Penance, Holy Fire) when you get good CC on an opponent who has no outs, and your kill target has no defensives (or defensives you can dispel ie. Paladin/Mage).
Druid specific, make sure you dispel Innervate, it's a 3 minute cooldown that restores 20% of the Druid's max mana. It's icon is a blue lightning bolt (http://www.wowhead.com/spell=29166).
Try to purge off the Druid's HoTs before you go for bursts (before being the important part, Lifebloom procs a considerable heal when it's dispelled), not only does it cost him mana to reapply them, but it also costs a lot of time time: 4 GCDs. You'll also potentially cause them to use even more mana (or important CDs) as they'll likely have to use Regrowth (Druid's Flash Heal) to stabilize their/their partners HP. Druid are very weak to hard swaps onto targets with no HoTs. If you can fear a Druid out into the open while he has no HotS and Barkskin on cooldown, then swap to him in a stun and CC on his partner, your partners offensives and Fiend from you, there's a very good chance he'll die.
Thank you for the tips Cedrich! Some good pointers there. I have a lvl 90 druid, but only ever play as feral/guardian, and is only used for professions. I know of most of their abilities, but the ins/outs/tricks with some of their abilities I do not know. One thing I do not do much of is offensive dispells (purge). This week I think I will start focusing on this, and working out what I should purge on different opponents.