Many on-use trinkets work like meta-spells. Take Ephmeral Snowflake.
Types of meta-spellsI'm going to divide meta-spells into three categories.
The first category includes activated spells, talents or items with a cooldown. Example: Inner Focus.
The second category include talents (generally) that grant a limited duration effect when casting certain spells. Example: Borrowed Time.
The third category include passive procs, generally from items. Often has an internal cooldown of 45 sec or stacks up multiple times. Example: Binding Stone stacks up a buff, while Althor's Abacus is a proc with a 45 sec internal cooldown.
Meta-spells by classAll healers have meta-spells. Even if I've played all four healer classes at 80, I easily forget some spells. Here's those I remember.
- Nature's Swiftness: Many use this simply as another heal in their repertoire combined with Greater Healing Wave.
- Spiritwalker's Grace: Cast spells while moving. Doesn't improve theoretical output.
- Unleash Elements, the Earthliving Weapon version. Increases the next heal by 20%. It has so short cooldown it's doubtful whether it belongs here.
- Bloodlust (or Heroism): Also rather special, as it has a very long duration and cooldown for such a spell.
- They also used to have Tidal Force, but I can't find it in the current talent tree. Perhaps it was removed in 4.0.
Druids have one spell: Nature's Swiftness. I don't know about anyone else. Okay, if you really want to count it: Barskin.
Priests have Archangel, though it's rather special in the way it works since it requires you to cast Smite before this has any effect.
Discipline priests also have Inner Focus, as mentioned above, and Power Infusion. Complete with cool graphics. Holy priests have their signature spell, Chakra, which changes how certain other spells work. However, it can have 100% uptime, so you don't want to save it for any purpose.
Paladins have several meta-spells that can be combined together.
- Avenging Wrath: 20% more healing. Oh, and pretty wings. Ooh! Shiny!
- Divine Favor: +20% haste, +20% spell crit.
- Guardian of Ancient Kings, the holy variant Ancient Healer. Casts Light of Ancient Kings. Against a single isolated target, it doubles your healing. More if there are other allies nearby.
In addition, all classes can have on-use trinkets. Lifeblood, the granted ability from Herbalism, activates a 20-sec internal cooldown with on-use trinkets.
The challenge with meta-spellsMeta-spells can be very powerful. They can significantly improve the throughput of your spells. However, they can also be completely wasted. You may activate your meta-spells only to discover that there were no need for them, and waste the CD. Worse, you may wait for the perfect opportunity to use, only to forget to use it when you really really need it.
To be the best healer you can be, you need to remember to use your full repertoire of spells, including meta-spells.
A big challenge of meta-spells is finding out how you want to combine them. My paladin has herbalism, and so always has access to Lifeblood. That gives me 4 on-use meta-spells. I can use them separately, and I can combine them.
Combining them all gives me +20% healing, +20% haste, +20% crit, +480 haste, and my next 5 heals are duplicated and also splashes to nearby targets. That at least doubles my throughput, possibly triples it. Phew.
However, if you don't count Valithria Dreamwalker, it is rather likely that stacking so much healing at once will result in a lot of overhealing. So it's probably better to not spend everything at the same time.
I still need to figure out how to best combine my cooldowns. Add to that they have different cooldowns, so macroing two abilities with different cooldowns means that I'll either wait for both to come off cooldown before using them, wasting one of them, or spend them separately after the first time. Which isn't necessarily such a bad idea.
With that said, I love the feeling I get when I blow all my cooldowns (often while having Concentration Aura and Aura Mastery or Divine Shield up) while healing left and right in a hectic battleground fight.
I've also had much fun actually being able to kill something as a healer. All the paladin cooldowns except Guardian of Ancient Kings work on Exorcism too. Yay! I can kill stuff! ... and I call myself a healer.