Wednesday, October 7, 2009

Power Infusion is Better than Heroism

Although I've been reviewing talents, I hadn't intended to review Power Infusion. It seems like a straightforward spell, a good buy for one point, and I've never seen a Disc priest without it. But lately I've seen some discussion on it, specifically whether it was worth casting on yourself or a DPS. Someone even said it was nothing to write home about! Because of this, I wanted to share some thoughts.

Before I justify the claim that PI is better than Heroism, here's the obligatory basics. Power Infusion speeds up casting and decreases the cost of spells. It provides a noticeable 20% increase in casting speed for 15 seconds, and saves some mana too. It is similar to Heroism/Bloodlust (with which its speed does not stack). It also doesn't stack with Arcane Power for mages.

Give it Away, or Keep it?

So PI gives haste and saves mana. No caster can argue with that. But how best to use it, casting it on a DPS, or saving it for oneself?

First, let's look at ourselves. When it comes to spell haste, Disc priests are often swimming in it. We'll often have Borrowed Time active for half of our spellcasts or more. And when it comes to mana, Rapture is usually ticking regularly. Now there are certainly times when predictable burst healing is needed, and casting PI on oneself can help. It is also very nice for General Vezax, for example. But more often than not, it can be superfluous on a Disc priest.

So, let's look at dropping it on a DPS. They'd probably enjoy some haste, they love Heroism after all! Comparing the two, we see that PI gives only 2/3 of the casting speed bonus, and for 15 seconds instead of 40. So one cast of PI on a DPS is about (2/3)*(15/40) as good as Heroism, that is, 25% as good (not counting the mana savings, since DPS rarely go OOM in an ideal world).

However, PI has a nice short cooldown. In fact, with Aspiration, it's just 96 seconds. This means you can easily cast PI on a given DPS four or five times during your average fight. If we add that up, now we're talking 100-125% of the bonus of a Heroism. That's right, for one lucky DPS, Power Infusion is better than Heroism. Or put another way, your DPS of choice gets two Heroisms per boss. Hax!

The Fine Print

Now, although PI can help a given DPS's performance more than Heroism, there are some limitations. Heroism is easy for DPS to make use of, since it's often called for by a raid leader at a set time, during a solid burn phase. It also comes with graphical and sound cues and lasts 40 seconds, so it's easy for DPS to stack other trinkets and procs with it.

Power Infusion, on the other hand, will be up for four or five separate 15-second periods, and the timing is controlled by a priest who may be frantically healing. So here's some ideas to help people make the most of PI:

  • Pick a class that can benefit from the haste, like a mage or warlock.
  • Pick a player that can handle stacking cooldowns and procs for max damage.
  • Ideally, pick a player who knows in advance that your PI is coming.
  • Use PI during burst damage phases, or at least times when your DPS player can focus on casting.
  • But also use PI early and often, to get the most out of it.
  • Don't use it during phases when Heroism is usually called for. Try to stagger it with Heroism.
  • Use a macro to tell someone that you PI'd them. My macro is below.

Power Infusion Macro

Here is what I use to buff people, and tell them I did so. It casts PI (if in range and available) and whispers the target. It is 255 characters; I lengthened it because when it just said "You have [Power Infusion]," occasionally I would get a reply like "No, I didn't spec for it." Now my macro is a little more descriptive. (I would attach a "DPS for Dummies" book if I could!)

#show Power Infusion
/script local u,p="target","Power Infusion";if IsSpellInRange(p,u)==1 and GetSpellCooldown(p)==0 then SendChatMessage("You have "..GetSpellLink(p).." for 20 secs! Enjoy the haste!","WHISPER",nil,UnitName(u)) end
/cast Power Infusion

Something to Write Home About

So, overall, I am a big fan of PI. Back when it was the top-tier Disc talent I developed a "meh" feeling about it, since there's not much synergy with Disc (or with healing in general), but since then I have come to see its power. Blizzard keeps saying they won't give Heroism to another class, but really they've already given us a single-person version. Just find a smart DPS player to routinely PI, and pretty soon you will be receiving pleading tells to stay Disc instead of swapping to Holy or Shadow for any fights!


  1. Holy pally! Give it to the holy pally! Holy crap, I love me some infusions. They're so tasty, yes they are~

  2. Your math is incorrect. If it's 25% as effective as Heroism for the ONE dps you put it on, that ONE Dpser would get 25% more benefit if you put it on them 5 times during a fight, yes, not 125% more benefit. It's only 25% as good for each time you use it according to your math. Heroism affects the entire raid, not just one DPS, so its comparing a raid wide effect to a single target effect. A 2 tank, 3 healer fight has 5DPS left in a 10 man, so it's automatically 375% more effective for your raid dpsers, not to mention the dps your tanks are doing, which is not neglible anymore these days, than PI being used on one DPS 5 times in a row. It's obviously a great little booster though. Plan it with a DPS that will benefit your raid the most by having it on them and they utilize their dps cooldowns in conjunction with PI, uber.

  3. Actually, the math is correct. I don't claim that PI gives 125% more benefit, nor that PI is better for the whole raid than Heroism. I simply said that, for one DPS player, Power Infusion gives "100-125% of the bonus of a Heroism."

    Now that being said, of course we agree that PI and Heroism are both awesome and both have their uses, and that PI can be used to great effect in conjunction with a cooldown-popping DPS player. :)

  4. Would you care to comment why you shouldnt use it when BL is active?

  5. Basically, Power Infusion doesn't stack with it. The target gets cheaper spells, but the haste bonus (the main reason to cast PI) does not stack with Heroism/Bloodlust.