WHAT
Power Infusion
Infuses the target with power, increasing spell casting speed by 20% and reducing the mana cost of all spells by 20%. Lasts 15 seconds.
2 minute cooldown (lowered to 1.6 minute with 2 points in Aspiration) Does not trigger the GCD.
HOW
I’m a big mouseover macro fan, as clicking on someone to target them, then clicking on a spell is too slow and unwieldy. It’s also good practice to notify someone they’ve received Power Infusion because even though they should notice the animation and the buff, they might not (and/or might not realize what Power Infusion does.)
The following macro casts PI on your mouseover target and sends them a whisper:
/cast [target=mouseover] Power Infusion
/script local n,r=UnitName”target”;if(r)then n=n..”-“..r;end;SendChatMessage(“Power Infused! +20% haste at -20% mana for 15 seconds. Go!”,”WHISPER”,nil,n)
Penance Priest has some other macro ideas, including the addition of quartz cooldowns and error checking.
WHO
As Power Infusion gives the recipient increased casting speed at a reduced mana cost, the spell should obviously be cast on someone who a) casts spells and b) uses mana. Duh. When determining who will benefit the most from PI, consider a) who can use an increased casting speed and b) who can use the break on mana consumption. Duh +1.
Although I’ve read some suggestions that Disc Priests use the buff solely on themselves (and have raided with a Disc Priest who did just that), I think it would be a difficult argument to make that a Disc Priest needs help with mana. (Maybe if you’re undergeared? Maybe if you’re healing a heroic with 4 melee who won’t step out of whirlwinds? Maybe if you’re using spells that don’t proc Rapture?) If you feel you are struggling with the healing in a particular encounter, then by all means, buff yourself. Otherwise, I’d recommend buffing someone else.
I don’t use Power Infusion as an “Oh shit!” button for more healing, but rather as a “Hell yeah!” button for a high-dpsing caster. Consensus seems to be that mages are the best recipients of PI — they get the most bang-for-the-buck from the haste and the mana reduction. However, depending on the makeup of your raid and the DPS of your caster group, you might chose a different target.
I don’t use Recount, and I don’t monitor the DPS of a fight, but if I don’t know my fellow raiders and don’t have an established target, after the first encounter, I always ask Kaleyen who the top caster and the top mage were so that I can gauge who gets PI. If appropriate, I’ll Raid Leader if they have a preference for who receives it.
Mages who respond to my PI whisper macro with “??” do not get the buff again. Mages who respond to my PI whisper macro with “omg i love you” do.
WHEN
Power Infusion does not stack with the mage talent Arcane Power, and the haste portion of the spell does not stack with Heroism/Bloodlust. You’ll want to track these spells so you aren’t wasting a cooldown. You can use the addon Need to Know to track the latter. I use Grid to track Arcane Power on mages (See this post for help on setting up Grid). If you try to cast PI on a mage who has Arcane Power up, you will get the “a more powerful spell is active” error message. The mage will, however, be able to override PI with Arcane Power.
It’s also worth having a conversation with your casters to ask about their preference for receiving the spell. Good DPS have their casting rotations down to a science, and they’ll be able to tell you when the buff would most benefit them. For example, the mage Mirror Image ability reduces a mage’s threat, and so Mirror Image and Power Infusion work well together as the mage will be able to pump out the extra DPS without the risk of pulling aggro. This spell is often their opening salvo, and if so, you should cast PI on them right away. (I need to figure out a better way of tracking when a mage has Mirror Image active — other than, ya know, looking at the screen)
With a 1.6 minute cooldown, one can cast Power Infusion a lot over the course of a raid. (You can use WWS to check the “uptime” of the spell. For help with WWS, check here.) This is something I’m trying to improve in my own gameplay, making sure that PI gets worked into my “rotation” regularly.